22nd World Gas Conference June 6 - 9, 2006, Amsterdam, The Netherlands
Report of Study Group 5.4
“Distributed Energy : from CHP to micro-generation”
Report du group du study 5.4
Distribution de energi de etude:
Chairman/President
Samuel Bernstein
ABSTRACT
In this report is detailed the work undertaken by the IGU Study Group (SG) 5.4:Distributed Energy Re-sources (DER): from CHP (Combined Heat and Power) to micro-generation. DER is defined as the generation of electrical energy in the proximities of the consumption centres, or even in the own consum-ing installation. This applies to Renewable power plants and Co-generation, Tri-generation and the Dis-trict Heating & Cooling. DER technologies contribute in a very significant form to the reduction of CO2 emissions to the atmosphere and to energy savings and efficiency. The technology represents a new market opportunity and business to the energy companies and to the gas companies in particular. This report presents a synopsis on DER/CHP business issues, example of installations in several countries and a useful reference guide for further information on DER on the internet. The IGU SG 5.4 has spent con-siderable efforts over the past three years in evaluating the technology, the business issues and the pro-gress of the technology. The general feeling of the SG has been that by looking at various examples of projects, interested professional could draw their own conclusions for new installations. Finally the SG has presented numerous papers in international meetings and magazines to promote a healthy dialog on the subject of DER.
RESUME
Ce report détaille les travaux entrepris par le groupe de travail 5.4 de l’UIIG. Les Ressources Energé-tiques Distribuées (RED): De la production combinée de la chaleur et de l’électricité (PCCE) à la micro-génération. RED se définit comme la production d’énergie électrique à proximité des centres de con-sommation ou même dans leur propre installation de concon-sommation. Ceci s’applique aux centrales élec-triques fondés sur des énergies renouvelables, à la trigénération et à la microgénération. Les technologies RED contribue considérablement à la réduction des émissions de CO2 dans l’atmosphère et aux
écono-mies d’énergie ainsi qu’au rendement. La technologie représente un nouveau créneau et des activités commerciales pour les entreprises d’énergie et en particulier pour les entreprises de gaz
TABLE OF CONTENTS
1. Abstract2. Foreword by the chairman
3. Distributed energy resources technologies & Business perspectives. A new market opportunity for en-ergy companies.
4.Case studies for Gas Fired Cogeneration & Distributed Power Production
5. Internet Links concerning Gas Fired Cogeneration & Distributed Power Production
Appendix 1: Members of Committee
FOREWORD
Distributed Energy Resources (DER or DG) offers an important new concept for the electricity business and interesting new market opportunities to energy companies against the background of the liberalization of energy markets. It offers a new market to the gas industry and has the potential to reduce polluting emissions and contribute to energy savings and efficiency.
From a customer perspective there is the potential for an improved energy service with better reliability and more cost effective product.
Over the past several years the DER technology has improved significantly and numerous participants have been exploring an appropriate business model for DER. Even though the specific conditions in eve-ry counteve-ry are different, the following characteristics of DER elements have been generally accepted:
• It reduces the losses of energy in the systems of electrical transport and distribution • It reduces to the investments in new systems of transport of electrical energy
• It reduces the air emissions to the atmosphere and helps in attaining the agreements of the Kyoto Protocol, by applying renewable energies or co-generation systems.
• It enhances the promise of power quality provision.
• DER provides a good tool to improve the power delivery and environmental problems.
Nevertheless, the development of the DER will depend to a great extent on the legislative input and sup-port. The energy business in most countries is highly regulated and the business reward depends on the specific criteria established by the regulating body. As such the energy business does not operate strictly in response to free market opportunities. In that regard it is important to consider that the liberalization of the electrical markets is changing the rules of these markets, with simultaneous threats and opportunities for the DER.
In the following the IGU SG 5.4 presents a synopsis on the DER technology and business issues, exam-ple of DER installations in several countries and a useful reference guide for further information on DER. The IGU SG 5.4 has spent considerable efforts over the past three years in evaluating the technology, the business issues and the progress of DER. Several site visits were conducted to look at different installa-tions around the world. The general feeling of the committee was that by looking at various examples of projects, interested professional could draw their own conclusions for new installations. Finally the com-mittee presented numerous papers in international meetings and magazines to promote a healthy dialog on the subject of DER.
Special thanks are due to all the members of the Committee (Appendix 1) who voluntarily contributed their time, effort and knowledge to promote the exchange of knowledge regarding DER. In particular I would like to acknowledge the contributions of Mr. Fidel Valle, Vice Chairman of SG 5.4 Committee (ES), Mr. Aksel Hauge Pedersen, Secretary (DK) and Mr. Jan de Wit, Member (DK).
DISTRIBUTED ENERGY RESOURCES TECHNOLOGIES & BUSINESS
PERSPEC-TIVES
DISTRIBUTED ENERGY RESOURCES - DER
The present form of the electric systems is based on the generation of the electrical energy in centralized power plants of considerable sizes, the transport of electric power over considerable
dis-tances through networks of high voltage and finally the distribu-tion of the electrical energy to the final consumer, using sys-tems of decreasing voltage in line with the customer demand.
The tendency of world wide electrical demand in the last few years can be characterized by the following fundamen-tal aspects:
• A continued increase of the energy and electrical power demand;
• The expectation to have high quality power delivered with no interruptions over long periods. In other words, the customers expect to have a stable supply (without voltage sags) of uninterrupted clean electric power (with no harmonic disturbances).
If, in addition, we take into account the real efficiency of the present electrical generation mix and the losses of the transport and distribution facilities, the overall efficiency of the system as a whole is not high.
The conventional model of generation and electrical distribution begins to show symptoms of difficulties in fulfilling its missions. In addition the modern solutions for generation and transport of electricity are expected to be environmentally responsible and are to be as sustainable as possible.
The blackouts experienced in the second half of 2003 in North America and in Italy, present a common problem in which the power failure is not caused by a lack of generation capacity, but by the failure of some of the transportation lines that are to deliver electrical energy from remote plants of production to the markets.
These cases, although singular, are indicative of the vulnerability of the traditional electrical system to growth in demand and the associated need to transport large volumes of power over the ag-ing electric grids.
The Distributed Energy Resources (DER) or distributed electrical generation appears like a good solution to this problem. In this context, the DER includes renewable energies and high efficient co-generation – Combined Heat and Power (CHP) - as well as its extensions like Trigeneration and District Heating & Cooling. At the same time, the construction of centralized power stations of Com-bined Cycle also provide reliable power at much higher efficiency compared with the present inventory of centralized power plants.
The concept of DER is applied to an integrated electrical system in which a fraction of the en-ergy is generated in decentralized units, dispersed and next to the consumption points, although there does not exist a homogenous definition of DER and its range of plant sizes.
In any case, all the sources agree that Distributed Energy Generation (DEG), distributed ener-gy (DER or DE), distributed generation (DG), distributed resources (DR), or dispersed power (DP) in-cludes electric generation technologies of small-scale power generation located close to the load be-ing served.
Historically, the first units of electrical production around the world followed principles which today we would classify as distributed generation, despite of different size of present DER facilities. It
Worldwide transmission and distribution (T&D) losses to-taled 1,336 TWh in 1999 (dates according to Electricity
Infor-mation 2001, International Ener-gy Agency), the equivalent of
11.6% of the world’s final elec-tricity consumption – or more than the combined electricity demand of Germany, the UK, France and Spain. Including losses from T&D systems, the worldwide waste of energy aris-ing from central power is very close to the total amount of en-ergy consumed by the global transportation sector.
World Survey of Decentralized Energy – 2002/2003 WADE – World Alliance for
is to say that these plants covered their own requirement and sold their excesses power to the neigh-boring industries.
Nevertheless, the direction of the electrical industry, at least from World War II, has been to-wards obtaining economies of scale. Larger plants provided better economies and yet these plants were progressively moved away from the centers of consumption. In addition, large interconnecting grids were formed and the electric system control and delivery centers were transferred from the local area of smaller clients to big public, or private, management organizations.
In general, the promise of the DER offers the following advantages in comparison to the tradi-tional model:
• It reduces the consumption of primary energy, due to the greater efficiency of the pro-cess (using several forms of energy e.g. CHP), and on the other hand, it avoids the losses of energy associated with electrical transport and distribution;
• It reduces the emissions of polluting agents to the atmosphere collaborating to the at-tainment in the agreements of the Kyoto protocol;
• It provides the means to reduce, or at least to delay, the investments in new infrastruc-tures of distribution of electrical energy;
• It avoids investments in additional capacity of centralized generation; • It offers an electrical provision of quality.
The necessity to install new capacity of electrical energy to meet the increasing demand, the quality of provision like an es-sential factor for the companies in the new economy and the increase of the interest in the reduction of the emissions and increase in electric generation efficiency as described in the Kyoto Protocol, entails the necessity to accelerate the use of high efficiency gen-eration technologies and reduce losses and emissions within a system in which the DER can play a very significant role.
Figure 1: The Kyoto Protocol pillars
TECHNOLOGY PERSPECTIVE
DER is supported by a vast array of technologies, some already mature, and some emerging technologies that offer a great future potential. The range of DER technologies is summarized in the following figure:
Figure 2. DER technologies
Basically, the technologies of DER electrical generation can be grouped in two basic types:
• Fossil fuel technologies: internal & external combustion engines, gas turbines, micro-turbines and fuel cells
Greenhouse-effect gas emissions reduction
Energy efficiency
improvement Energy savings
The Kyoto Protocol
•Interconnection •Microgrids •Interconnection •Microgrids Renewable Energy Sources •Interconnection •Microgrids •Interconnection •Microgrids
Gas Turbines (GT) Microturbines (GT) Fuel Cells (FC)
• Renewable Energy Technologies: Photovoltaic, wind energy, biomass and small-scale hydropower.
It is important to note that the renewable sources depend on an unpredictable generation schedule (e.g. wind, sun) not being able to provide power guarantee at all times what may increase the difficulty of the electric grid management. Therefore the integration of conventional energies is re-quired.
Obviously, most electrical DER applications also require interconnection with the grid. Inter-connection technology and cost are very critical to the acceptance of the DER applications in the grid and its impact on power stability, and control.
In the residential and commercial sector and in applications of District Heating & Cooling it is important to consider thermal energy storage technologies (typically tanks of hot water, cold water or ice). Energy storage serves to smooth demand peaks and avoids additional capacity, which would be redundant most of the time. On the other hand additional space and investment is required, and oper-ation of the system gets more complex.
Fossil Fuel Technologies
- Internal Combustion Engines (ICE):
The reciprocating internal combustion engines (ICE) offer reliable and mature equipment wide-ly used in CHP systems. This equipment is available in a wide range of capacities (between 1 kWe and 20 MWe) and can utilize a wide range of liquid and gaseous fuels.
ICE have an electrical efficiency between 25 and 45% (LCV). When thermal energy is cap-tured the total efficiency of the co-generation system is normally between 65 and 85%; in units operat-ing with flue gas condensation the overall efficiency could be above 95% (LCV).
The thermal utilization of ICE technology is of some complexity in certain applications due to a relatively low temperature output available. Also, it must be considered the division of the available heat, on one side from the exhaust gases and on the other side from the heat of the engine refrigera-tion circuits.
ICE are not as susceptible to external conditions like other technologies. In general, ICE have a 1% power loss for each 100 meter of altitude above sea level and a 1% loss for an increase of 5.5ºC in room temperature.
At the same time ICE are considered to have relatively higher maintenance costs and higher emission than other DER technologies.
They maintain its efficiencies over a wide rage of partial loads.
The objective of current research work in ICE is to obtain engines with efficiencies of 50-55%, a reduction in the generation of NOx and an increase of the reliability to reduce maintenance. Topics of research include fuel injection, the design of the valves, head of the cylinders, combustion chamber design.
- Gas Turbines (GT):
Gas turbines, in the above mentioned power range, show efficiencies between 32 and 46%. But in comparison with ICE, gas turbines provide a worse efficiency at partial loads.
External conditions also have an influence on gas turbine performance. In general, a 3.5% of efficiency is lost for each 300 meter above sea level, although, the determining factor is the ambient temperature. A 0.9% of efficiency is lost for each ºC above the ambient temperature at sea level.
The research work in gas turbine includes: Obtaining 60% efficiency or more, reduction of emission of NOx and CO, and the durability. Topics of current research are centered on the develop-ment of new cycles, including regeneration and intermediate cooling stages and the developdevelop-ment of new materials.
- Microturbines (µGT):
Microturbines are gas turbines with special construction characteristics and capacities be-tween 25 and 300 kWe. They can also operate diverse fuels like natural gas, propane, biogas and liquid fuels.
The core of a microturbine system includes a generator, a compressor, a combustion chamber and a turbine. All of them are in general on the same axis that rotates in the range of 60,000 and 100,000 rpm. There were also microturbines with design of multiple axles rotating at different speeds although these were not yet commercialized.
The electricity is generated at high frequency in the generator and then it is rectified for a final electric frequency of either 50 or 60 Hertz. The power quality (electric frequency) of the generated power is considered very good.
The electrical efficiency of microturbines lies between 25 to 30%. The individual units can be combined in a modular installation for a larger power capacity.
The commercial offer of microturbines is still limited and investment level is still elevated. Nonetheless in a near future installations based on microturbines can offer an attractive solution for DER in buildings and for small applications.
- Stirling engines
Stirling engines are powered by the expansion of a gas when heated, followed by the com-pression of the gas when cooled. The Stirling engine contains a fixed amount of gas which is trans-ferred back and forth between "cold" and “hot” ends. A "displacer piston" moves the gas between the two ends and the "power internal piston" changes the volume as the gas expands and contracts.
The Stirling cycle uses an external heat source, which could be anything from fossil fuels to waste heat. Combustion takes place outside the cylinder and in principle can be well controlled to re-duce emissions. There are two types of Stirling engines including a ‘free piston’ and ‘kinematic Stir-ling engine’.
The main advantages of the Stirling engines are:
- The external burning can be accomplished with multitude of solid, liquid, gase-ous, hydrogen and biomass fuels, or solar energy
- The continuous combustion process can be used to supply heat, while reducing emission of unburned fuel. The emissions are significantly less than in other thermal engines.
- The major heat fraction of a Stirling motor is being extracted by the coolant wherefore it represents an attractive possibility for CHP applications.
Since these engines show high thermal efficiencies they are most suitable for applications where thermal requirements are significant, for example in geographical regions with a high annual heating demand. They are not adequate in geographical regions with a small thermal demand.
They are generally found in small sizes (1 - 25 kW) and are currently being produced in small quantities for specialized applications. There are many companies developing Stirling devices for niche markets, such as cogeneration units and power generation using alternative fuels.
The electrical efficiency is about 12 – 20%, with the target of higher efficiencies than 30%.
- Fuel cells
Fuel cells are an emerging technology of electric generation on small scale whose capacity depends on the type of cell and can vary between 1 kWe and 10 MWe.
In general, a fuel cell is based on the inverse principle of the electrolysis. That is to say, elec-tricity is generated from the combination of hydrogen and oxygen to water without combustion taking place. As it is an exothermic process, applications of CHP can be made.
A detailed classification of fuel cells includes the following:
AFC - Alcaline Fuel Cells
AFC was the first fuel cell for space applications. The operating temperature of AFC is of 90-100ºC and that is the reason why it is not readily used in co-generation. Hydrogen for AFC must have very high purity, since the CO and the CO2 (even from atmospheric air) are poisons. Therefore, AFC requires an expensive process of elimination of these compounds from the H2 and the air. On the oth-er hand, AFC is a reliable technology, with a good electrical efficiency (~60%) and of which thoth-ere is ample experience in space and military applications. However, the purification costs make the AFC not suitable for DER applications.
PEMFC - Polymer Electrolyte Membrane Fuel Cells
Operating temperatures lie between 60 and 100ºC (exceptionally 180-200ºC). Hydrogen of great purity is required and an electrical efficiency between 30 and 40% can be achieved. The low temperatures of operation, the short time necessary for the starting and lightweight and their simplicity makes the PEM attractive for automotive application. The heat recovery for CHP applications is by producing hot water.
PAFC - Phosphoric Acid Fuel Cells
It is a relatively more mature than other fuel cell technologies. It uses Platinum catalyst, and it is susceptible to the price of this metal. At temperatures of 200ºC there is a vast experience on in the use of PAFC fuel cells. At the same time it appears that there are no possibilities to significantly im-prove the PAFC performance or to reduce its first (capital) cost. PAFC provides efficiency of 36-42%. Also, the heat recovery for CHP applications is by producing hot water.
MCFC - Molten Carbonate Fuel Cells
SOFC - Solid Oxide Fuel Cells
It offers the same advantages than the MCFC with thermal advantage and electrical efficiency (~45 - 60%). When operating at higher temperatures (800-1000 ºC) it allows using a greater variety of fuels. SOFCs are also the most sulfur-resistant fuel cell type; they can tolerate several orders of mag-nitude more sulfur than other cell types. In addition, they are not poisoned by carbon monoxide (CO), which can even be used as fuel. This allows SOFCs to use gases made from coal. As it is a high tem-perature fuel cell, the heat recovery can be as hot water, low-pressure steam or high-pressure steam. It also has a relatively quick start-up compared with that of MCFC models.
All types of fuel cells mentioned above are commercially available only as demonstration products for the time being; its reliability and durability must be improved.
The fuel cells that offer the highest opportunity for a greater development is expected to be the PEM for transportation, residential and mobile applications. The SOFC offers an interesting promise for DER applications.
The high temperature fuel cells (MCFC and SOFC) can be fed directly with natural gas since the high temperature allows an auto reforming process so that the necessary hydrogen is internally generated. On the other hand, in the low temperature fuel cells an external reformer is needed to gen-erate the hydrogen.
Renewable Sources Technologies
- Photovoltaic Energy
Photovoltaic (PV) cells directly convert light from the sun into electricity. Usually fabricated from silicon, PV cells utilize solid-state semiconductors.
Historically, electrical PV cells were already used in situations where power from the grid was unavailable, such as in remote areas to power systems, satellites, and handheld calculators.
By connecting several solar modules, electricity can also be supplied to the low voltage grid.
Efficiencies for commercial PV cells range are from 7-17%. It requires approximate surface of 10m2 to produces 1kW; thus, big surfaces are required for PV applications.
Although once in service, PV is considered a “clean” renewable technology, a ‘cradle to grave’ analysis (life-cycle analysis) shows that the fabrication process of PV cells is environmentally debata-ble.
Inversion costs for PV cells are still too high; however research efforts are aimed to lower these costs. Due to existing incentives and subsidies, implementation of PV cells has reached until now a considerable level.
- Wind Energy
The kinetic energy in the wind is a promising source of renewable energy with significant po-tential in many parts of the world.
The wind speed is not constant in any location and therefore, the energy that can be captured by wind turbines is highly dependent on the local average wind speed.
The wind speeds at which wind turbines commonly operate are between 2.5 and 25 m/s. Thus, wind power can become unavailable at times of low wind speeds, but also at times of very high wind speed, when wind turbines need be shut down to avoid damage of equipment.
Scaling of wind turbines over the classic 1.5 to 1.65 MW is a possibility, although the logistics of handling such large units on land have become quite difficult. Tower diameters should preferably not exceed 4.2 or 4.4 metres, if they are to be transported in normal sections by road or rail.
- Biomass
The basis of biomass energy is the utilization of organic matter, in most cases plants and trees residues.
In the industrialized countries, with high-density population, the limited availability of free or usable land limit a resource like biomass, to be only a complement to the conventional generation of electricity. There is a trend towards increasing biomass crops applications.
In the future, fast-growing energy crops may become the biomass fuel of choice. At the same time, biomass can also be collected as a by-product and residue from forestry, industry and household waste.
- Small Scale Hydro-Power
Generally speaking, small-scale hydropower are installations smaller than 10 MW.
The small-scale hydro installations usually utilize ‘run of river’ schemes where the river water is not stopped. Therefore small hydropower plants do not require massive dams or create the ecologi-cal threat of large hydro projects.
It is considered as a long-lasting and robust technology; systems can last for 50 years or more without major new investments. Power is usually continuously available on demand and it does not consume but only uses of the water, after its use for power generation, it is available for other purpos-es (although on a lower horizontal level).
Obviously, the viability of small hydroelectric power is highly dependent on the availability of water and it is strongly affected by the water resources cycles from year to year. Thus, although hy-dropower represents a significant potential world wide, its application is restricted only to geographic areas with significant water resources.
Below, in table 1 it is a summary of the main aspects of some of this DER generation technol-ogies.
ICE Gas turbine Gas
micro-turbine PV Wind energy Fuel cells (*)
Power range 1kW–20MW 500kW–50MW 25-300kW 1kW-1MW 10kW-5MW 1kW-1MW Fuel Natural gas, biogas, GLP or liquid fuels Natural gas, biogas, GLP or liquid fuels Natural gas, biogas, GLP or liquid fuels
Sun light Wind
Emissions once in service (ppm) NOx < 160 CO < 70 NOx < 25 CO < 50 @ 15% O2 NOx < 50 CO < 50 @ 15% O2 - - NOx < 1 CO < 2 Technology
sta-tus Commercial Commercial
Some com-mercial models
Commercial Commercial Pre -Commercial
(*) Given data is highly dependent on fuel cell technology analyzed
(**) Including the spacing between wind turbines. Data source: American Wind Energy Asso-ciation.
Table 1: Summary of main DER technologies (Sources: Adapted from “Generación eléctrica distribuida. Manual de diseño” - Distributed electric generation. Design handbook. gasNatural. 2005,
and data from SG5.4-IGU)
Interconnections and Microgrids
The interconnection system is the means by which the DER unit electrically connects to the universal electrical power grid, and it also can provide monitoring, control, metering, and dispatch of the DER unit.
Proper interconnection systems allow to:
• Operate the DER equipment in a prime power mode and supplement peak power de-mands with grid power purchases,
• Obtain backup power from the grid in the event of a DER system outage, eliminating the need for complete system redundancy,
• Take advantage of the opportunity to export power to the grid,
• Improve overall customer system reliability by providing an alternative power supply option,
There is a special concern worldwide about the interconnection of DER and the control of the resulting grid.
In general, there is a lack of experience and presently technical inability to control a significant number of DER units link to the same grid, thus requiring more research on dispatch real time models, dynamic models for several machines, real time operation and control, design of protection schemes.
Several research programs are aimed to enhance the knowledge on DER interconnections and its control. One example is the “Fenix” project, co-financed by the European Union in its 6th RTD
Framework Programme.
Work is also required in the standardization field, as there is a lack of standards and protocols to enable the integration of micro generation in the grid and in the market.
A new standard was developed by the US Institute of Electrical and Electronic Engineers (IEEE). That is the IEEE Standard for Interconnecting Distributed Resources with Electric Power
Sys-tems, IEEE P1547. The IEEE P1547 seeks to provide a uniform standard for requirements related to
the performance, operation, testing, safety considerations and maintenance of the interconnection.
Microgrids
The interconnection of small modular generation sources into the low voltage grid will form in future a new type of power system, the microgrid. Microgrids can be connected to the main power network or be operated autonomously isolated from the main power grid.
The microgrid can be seen by the utility as a controlled single unit of the power system.
There is a lack of legislation to frame the concept of microgrids in which there would be an as-sociation of a low voltage network, DER units and electrical consumers able to operate in an intercon-nected mode or in an autonomous isolated way.
This new scenario of operation requires the development of applied research at several levels to profit from the capabilities that this concept may offer and develop efficient strategies to manage microgrids. This includes dealing with microsource electrical modelling, power system low voltage op-erational impact analysis, control, power quality and network reliability, protection coordination and personnel safety, communications, economical and electrical market procedures, standards and regu-lations.
In this area it could be mentioned the “MicroGrid” project, co-financed by the European Union in its 5th RTD Framework Programme.
BUSINESS PERSPECTIVE
DER offers an important new concept for the electrical business and interesting new market opportunities to the energy companies worldwide.
DER breaks with the dominant model during 20th century in the electrical business, raises a
di-rect technological convergence with the sector of hydrocarbons and a didi-rect technological competition with the electric transport and distribution business. It is for that reason that numerous utilities, espe-cially those mentioned before, consider the DER like a fundamental strategic question for their future business.
It appears that a new business concept may be undertaken to provide high quality power ser-vices without the scheme of Centralized System and through its traditional distribution channels.
DER may be a new market to the gas industry especially when gas prices are rising and the traditional markets are threatened.
DER economics approach
Electric & Gas Utilities, including energy services companies (ESCO) and other non-regulated entities, and their customers are the main user groups most likely to deploy DER.
It is difficult to assess, even in general terms, the attractiveness of DER to utilities, since the economics vary widely based on the utility’s actual system configuration, the loads to be served, the national regulations and the market. Anyway, generally speaking, a utility can be expected to see DER as an additional option to meet load growth and relieve distribution constraints.
CHP in Europe
The energy policies of the European Union set out the objective that Cogeneration must increase its market share from the current 13% (*) to 18% by 2010, following an strategy of energy efficiency, en-ergy saving, more security in enen-ergy supply and re-duction of CO2 emissions.
Within this strategy on 11 February 2004 the Directive 2004/8/EC on the promotion of cogenera-tion based on a useful heat demand in the internal energy market and amending Directive 92/42/EEC was passed of the European Parliament and it is supposed to be transposed into national law within two years since its publication, i.e. before 21 Febru-ary 2006.
It is also interesting the Directive 2002/91/CE from 16 December 2002 on the energy performance of buildings in which Member States shall ensure that for new buildings with a total useful floor area over 1.000 m2 it is considered and taken into account be-fore construction the technical, environmental and economic feasibility of alternative systems such as: decentralised energy supply systems based on re-newable energy and CHP cogeneration).
This Directive should be transposed into the national laws before 4 January 2006.
It must also be emphasized the determined focus of the European Union on the Kyoto Protocol and the compromise made by the EU to reduce emissions of greenhouse gases by 8% in the period 2008-2010 from those of 1990. This can only be achieved by adopting energy efficiency and energy saving measures.
Source: Internal report. Gas Natural Group. 2005 (*) Data source: Cogen Europe 2005 Without these constraints, DER will likely
be more costly than a central plant option and therefore it cannot be considered as a cost-effective solution.
However, in those cases in which there is a national regulation restricting the transmission and distribution utilities from owning generation, it may be implied that they cannot own or operate DER. Then even in cases where DER is the most cost-effective option, it will not be chosen by the utility.
Unregulated players may adopt DER to reduce costs of their customers, provide additional services and export power to the grid. These companies might even position themselves to pro-vide DER at customer sites and aggregate this generation to compete in power markets.
For the end-use consumer, a simple anal-ysis of electricity prices, natural gas prices and DER investment and operation costs shows if a DER system is economically viable in a particular site.
Key interests of customers in DER in-clude:
• a way to reduce costs,
• to provide a reliable backup power • a high quality clean power.
Secondary benefits of DER include the fol-lowing potential benefits:
• Reduced fuel costs for steam, hot water, cold water loads through CHP systems
• Decreased exposure to electricity price volatility
• New source of revenues from electricity sales to the grid
• Improved power quality • Increased power reliability
DER benefits and added costs depend highly on the specific application, site, customer, utility, market particularities (climate, energy prices) and of course, on national regulations.
An extremely important factor with high influence on DER development is the energy markets liberalization with both positive and negative consequences. Liberalization allows access to the gener-ation market to different actors making a more favourable scenario for private initiatives different from the traditional utilities.
There is an additional risk related to liberalization, the risk of market prices influenced by ex-ternal factors and the difficulties for investors to foresee the future energy prices and therefore, the economic viability of projects.
One important initiative towards the DER business definition is The EU – DEEP (European Distributed Energy Partnership) project, co-financed by the European Union in its 6th RTD Framework
Programme. The objectives of the project are to design, develop and validate an innovative approach to identify promising business models (market+technology+financing) based on market requirements, which will amplify, from 2010, the large-scale penetration of DER in Europe.
Barriers to market penetration
Basically, there are three types of barriers to the proliferation of DER:
1. The management of the present electrical grid when a high amount of DER is con-nected
2. The legal frame (local, national or international) of application to each case 3. The economic factors and the structure of the markets to stimulate DER
1. Electrical Networks
• The electrical system is highly centralized especially in power distribution
• The large electrical companies generally envisage the DER as a threat to its tradition-al business
• When official aids are kept up in the traditional electrical business the market is dis-torted influencing directly DER options
2. Legal Frame
• Generally speaking, although the connection to the grid is normally regulated, it re-quires an additional negotiation with the Distribution company;
• The authorization process of facilities is quite complex and can take several months; • Heterogeneous and not well defined criteria in the minimum required efficiencies; • Particularities of the end-use of energy (industrial vs. residential-commercial) and/or
the generation technology used, not well recognized.
3. Economic Regime
• Inexistence of specific incentives, which accredit and remunerate the avoided electri-cal losses and investments in the distribution and/or transportations systems.
• Too few examples of specific incentives to reward energetic efficiency
• If a very high level of efficiency is demanded for all projects, DER could be discarded for several applications despite of consuming less energy than traditional systems; this occurred, for example, in residential sector where a significant difference between thermal and electric demands exist.
• Inexistence of a bonus for avoiding contaminant emissions
• Inexistence of an incentive for power generation during peak demand periods • Tax incentives and financial support for investments are limited
• The over-investment in residential-commercial applications in which heating recovery depends greatly on the climate and weather (heating and air conditioning), as in warm geographic areas, is not recognized;
Incentives to DER
As an answer to the identified barriers and conditioners, a se-ries of measures are suggested with object sets out to improve the sur-roundings in which the DER is based on the co-generation:
• To simplify the process of authorization of the facilities; • To regulate the connection to the distribution network
so that the access is made in previously well-known and not discriminatory conditions;
• The connection costs must be assumed by the genera-tor, nevertheless, it should be the distributing company who assumes, since being necessary, the costs de-rived from reinforcement of the network;
• To establish economic incentives to the DER based on two aspects:
• The recognition of the avoided losses in the network of transport and distribution, or, the correction of the en-ergy yielded to the network by means of a factor of losses avoided in the transport networks and distribu-tion;
• The recognition of the avoided polluting gas emissions respect to the conventional solutions of electrical gen-eration.
• To make flexible the demanded minimum efficiencies,
considering the alternative of conventional generation and the losses avoided in the mains thanks to the co-generations;
• In the case of small co-generations, and specially in the residential & commercial sec-tor, it should not be necessary to fulfill a minimum level of efficiency, being enough with generating a saving of primary energy respect to a conventional solution;
• To consider the climatic details of each country or geographic region and use of the fi-nal energy. For example, in cold climates, the thermal advantage is not the same as in hot climates there is greater demand of refrigeration and cooling than of heating. Also, it can not be compared the use of the thermal energy in an industrial application where the demand is depended on production schedule with residential market where the demand primarily depend on the climate.
Advantages of DER
Here it is included an adapted version of the benefits considered by the US Department of En-ergy (Strategic Plan for Distributed EnEn-ergy Resources, 2000) of DER, which generally speaking, are valid to all DER systems at an international level.
The success of the wind energy in Germany, Spain, and Denmark – countries which sum up to 80% of generated wind power in Europe – has been the result of the intro-duction of an attractive support system and re-moval of administrative barriers and of the evacuation to the grid.
Source: APPA – Span-ish Renewable Energy Producers Association, mentioning to the
CUSTOMER BENEFITS
• Ensures reliability of energy sup-ply, increasingly critical to busi-ness and industry in essential general and where interruption of service is unacceptable economi-cally or when health and safety is impacted;
• Provides the power quality needed in industrial applications that al-lows sensitive electronic instru-mentation and controls;
• Offers efficiency gains for on-site applications by avoiding line loss-es and using both electricity and heat produced in power genera-tion for processes or heating and to air conditioning;
• Provides to standby power option for area where transmission and distribution infrastructure does not exist or is too expensive to build; • Allows to power to be delivered in
environmentally sensitive area by having characteristically high effi-ciency and small pollutant emis-sions;
• Affords customers to choice in sat-isfying to their particular energy needs;
• Provides siting flexibility by virtue of their small size, superior envi-ronmental performance, and fuel flexibility.
SUPPLIER BENEFITS
• Limits capital exposure and risk because of the size, siting
flexibil-ity, and rapid installation time afforded by small, modularly constructed, environmen-tally friendly, and flexible fuel systems;
• Avoids unnecessary capital expenditure by closely matching capacity increases to demand growth;
• Avoids major investment in transmission an distribution system upgrades by siting new generation to near the to customer;
COUNTRY BENEFITS
• Reduces greenhouse gas emissions through efficiency gains and potential renewable energy uses;
• Responds to increasing energy demands and pollutant emission concerns while providing low-cost reliable essential energy to maintaining competitiveness in the world market;
• Enhances productivity through improved reliability and quality of to power delivered; • Enhances the electric system reliability;
7 GUIDING PRINCIPLES FOR EFFECTIVE ELECTRICITY MARKET REGULATION
1. There should be a fully independent and properly resourced regulator of the electricity system;
2. Electricity system pricing should be fully cost reflective with no cross subsidies from one part of the system to another;
3. Power generation and supply companies should have no ownership or management interest in the network;
4. All generators of electricity should have fair and non-discriminatory access to the grid;
5. Use of T&D networks should be priced ac-cording to the services they provide and not in such a way as to incentivise distribution companies to avoid DE interconnection;
6. Utilities should be required to engage in cost benefit analysis, which can enable DE to be de-veloped in areas where its local benefits outweigh the costs of constructing or upgrading new distribution facilities;
7. The electricity system should be subject to market based instruments, for example emissions trading, energy taxation and output-based standards, which fully reflect energy conversion efficiencies and internalise environmental costs of energy conversion.
Source: World Survey of Decentralized Energy – 2004
• Allows diversification in the energy supply and therefore, the reduction of foreign de-pendence.
Market Trends
The WADE (World for Alliance Decentralized Energy) in its "World Survey of Decentralized Energy - 2005", published a study on the degree of development of the DER. It includes the installed power already existent in the world
The WADE indicates that the co-generation represents a 96% of the total of the installed DER, with a worldwide average of a 7.2% on total the electrical generation.
DER share as % of total power generation
0 10 20 30 40 50 60 D en m ar k N et he rl an ds F inl an d R ussi a G er m an y P ol an d Jap an S pa in C roa ti a C hi na P or tug al C an ad a M exi co WO R LD U .S . U .K . Ind on esi a F ran ce B razi l Ind ia A rge nt ina
Figure 3: Development of the DER in the world in % respect to the total generation (Sources: WADE, 2005, Gas Natural Group 2004, M. Sunic CGA)
The countries leaders in this field are Denmark, the Netherlands and Finland.
The growth of DER depends, besides fuel prices, on environmental, legal and economical pol-icies of the different countries. Major growth market is expected in the EU, Japan and the USA. The following are the market trends in DER and cogeneration in several countries:
Denmark
Is the pioneer country for its capacities of cogeneration; DER represents more than 50% of its electricity generated. 80% of District Heating (DH: the predominant heating technology) is based on cogeneration. Decentralised and industrial cogeneration facilities signify more than 1800 MWe in-stalled. Danish legislation aims at environment protection, efficiency of energy uses and security of electricity supply. Present activities for lie now mainly in looking economic efficiency: many engines are being substituted by new more performed types.
Netherlands
Russia
Climatic conditions of this big country provokes that its electric generation is chiefly linked to CHP due to the considerably big amount of heat supplied by DH. According to the Russian Federal Office of Statistics (RFOS), electricity produced is around 932 MMWh/y and in this figure, CHP is in-volved in a 65%. In East Russia, coal is the main fossil fuel used, but in West Russia natural gas (ng), supported by oil, are the Primary Energy (PE) utilized; all together, ng represents now, about 64 % of PE.
The economic recession of late 90’s, but also recent better efficiency of facilities, have con-tributed to a reduction of ng consumption for CHP from 179 to 149 bln. m3 from1990 to 2004
Big energy stations (1000 to 4800 MWe) of CHP are recently started operating; but Combined Cycle units, in spite of its high efficiency, are scarce ( 0.5%), because they do not produce useful heat for DH..
Main barriers for the progress of DER are: the lack of adequate legislation and incentives, and also the lack of culture to invest in electric generation, in spite of very favorable ratio of prices for final energies.
However, due to the heat needs and the long distances between cities and also the growing productive centers activity, DER will have an important expansion especially in the range of 0.5 to 4 MWe. CHP growing expectations are 8% in next 5 years and about 20% in 10 years.
Germany
The German electricity market is the largest in the European Union. According to conserva-tive estimates there is a technical potential of DER to reach 50% of the electricity generation. The German government made CHP installations an important part of its national environmental and ener-gy security strateener-gy. But it showed only to modest impact on CHP. The market advances rapidly in the renewable energy fields as wind or biomass. The introduction of the "Law on the Conservation, Modernisation and Development of Combined Heat and Power" (KWKModG) in 2002 shows to slight impact to the CHP-market and it is supposed that small cogeneration installations plows becoming in-creasingly attractive.
France
At the beginning of the 90’s the power generation of cogenerations units were limited to 8 MVA but the payment of electricity produced was indexed to electricity sales price; till 822 MWe were installed.
In later 90’s funding was based on the “avoided costs” method, taking as a reference a com-bined cycles. Consequently, until 2000, new 3600 MWe were installed.
In last five years, despite of the electric purchase contracts for cogeneration have been ac-cepted up to 12 MWe, cogeneration has not grown as much as expected because of:
• Uncertainties about natural gas price and purchased electricity price. • Difficulties and cost of the grid connection.
Croatia
Recently in last five years cogeneration has increased considerably. At present the 675 MWe installed in different types of applications produces 14% of the total electricity generated last year in the country.
Slovenia
and excise taxes. Co-financing is offered for several phases of CHP introduction and subsidized loan are available for such projects; also licensing procedures are simplified for CHP projects.
In last decade, in addition to existed production, additional 40 MW are produced in 25 units of CHP: first sector is DH, followed by Services Sector and finally by Industry.
Spain
The growth of the co-generation in Spain had a special peak in the second half of the 90’s, but it has become paralyzed in the last years by a conjuncture of high prices of fuels and a legislation not too favorable to DER. It is hoped that with the recent regulation of the Special Regime of Generation (it includes cogeneration and renewable energies power plants), legal and economic surroundings for the co-generation will create favorable conditions and increase the capacity of DER in Spain. It is ex-pected that the increase will come from entering the residential and commercial markets. As for the renewable energies the actual Spanish legislation favors in special the aeolian energy and photovolta-ic. Therefore a spectacular growth of both technologies is expected.
Recently, two important strategic plans have been past and published by the current government with the pur-pose of enhancing the number of cogeneration and renewa-ble power plants. These documents are:
• Renewable Energies Plan in Spain 2005-2010 (Plan de Energías Renovables en Es-paña 2005-2010). August 2005. Ministry of Industry, Turism and Commerce.
• Strategy for Energy Saving and Efficiency in Spain 2004-2012. Action Plan. (Estrategia de Ahorro y Eficiencia Energética en España 2004-2012. Plan de Acción 2005-2007). July 2005. Ministry of Industry, Tourism and Commerce. Installed capacity 0 1.000 2.000 3.000 4.000 5.000 6.000 1996 1997 1998 1999 2000 2001 2002 MW ( mos t re s ourc e s ) 0 1 2 3 4 5 6 7 MW ( ph ot o v o lta ic ) Cogeneration Wind Energy Hydro-Power Biomass& residues Photovoltaic Installed capacity 0 1.000 2.000 3.000 4.000 5.000 6.000 1996 1997 1998 1999 2000 2001 2002 MW ( mos t re s ourc e s ) 0 1 2 3 4 5 6 7 MW ( ph ot o v o lta ic ) Installed capacity 0 1.000 2.000 3.000 4.000 5.000 6.000 1996 1997 1998 1999 2000 2001 2002 MW ( mos t re s ourc e s ) 0 1 2 3 4 5 6 7 MW ( ph ot o v o lta ic ) Cogeneration Wind Energy Hydro-Power Biomass& residues Photovoltaic Cogeneration Cogeneration Wind Energy Wind Energy Hydro-Power Hydro-Power Biomass& residues Biomass& residues Photovoltaic Photovoltaic
Figure 3: Cogeneration and some Renewable energies installed capacity in Spain (Source: CNE - Statistical Information of the sales of energy of the Special Regime)
China
China is expecting to continuing growth of the power demand. In order to be able to satisfy it, energy conservation including cogeneration was promoted by the government, but this program
re-The majority of the identi-fied barriers can be attributed to the existing legislative regimes which hardly recognize the ad-vantages of DER, in particular, environmental benefits, improve-ment of the electrical system and supply security in the major part of Europe. Thus, it is necessary that future politics in the electric sector recognize and appreciate the qualities of DER.
Decentralised Generation: Development of EU Policy
DECENT project. ECN (The Netherlands) -
IZT (Germany) –
COGEN Europe (Belgium) – RISO National Laboratory (Denmark),
cently ended. The Chinese are still investing in centralized energy systems and DER is seen as mar-ginal issue. Over 90% of generation in China is based on coal fuel. Coal increasing prices may en-courage DER with renewable energies and gas-fired cogeneration.
Japan
Japan’s power generation traditionally is mainly based on large-scale, utility-owned centrals of power systems. There has been a shift in governmental energy policy regarding Japan's Energy sup-ply indicating the importance of development and widespread uses of cogeneration and renewable energies. Figure 2 shows the resulting gas cogeneration systems in Japan. In the published long-term scenario “Outlook for Energy Supply and Demand in 2030” it is expected than approximately 20% of electricity will be generated by DER (approximately 10% (17GW) by natural gas). This target is furthermore supported by the introduction of three types of Green Power Systems:
• Renewable Portfolio Standard (RPS): to further the use of new energy
• Green Power Fund: to reduce CO2 emissions; to assist building PV and windmill to power plants
• Green Power Certification: to promote and incentive the uses of green to power
Figure 4: Growth of Gas cogeneration systems in Japan – Installed units (Source: The web site of The Japan Gas Association（JGA）published in 2005. Tatsuo Kume, Osaka Gas)
Canada
In total DER and CHP in Canada is about 11% of its power generation, this is divided more or less into hydro and cogeneration. Although there are still barriers in some of the energy markets to DER, the prospects are good due to multiple benefits of energy efficiencies and various tax benefits.
U.S.A.
credits for CHP. Concerns about system vulnerability of supply, worrying outages and rising power prices give in principle, the motivation for DER. The U.S. DOE set targets to cover about total 10% of the electric generation with cogeneration. US DOE plan calls for doubling the CHP capacity in the 10 year ending in 2010. Figure 4 presents the CHP applications by 2003.
Figure 5: CHP installations
in the USA
Most of the CHP applications have been in the larger capacity machines and numerous barri-ers exist to new CHP installations. In recent discussions and presentations by some of the electric utilities in the USA, they have expressed interest in exploring DER as part of the reliable electric grid of the future.
CONCLUSIONS
As commented before, the DER can be defined as the generation of electrical energy in the proximities of the consumption centers, or even in the own consuming installation. This applies to Re-newable power plants and Co-generation, Trigeneration and the District Heating & Cooling.
It is a fact that DER technologies have the potential necessary to contribute in a very signifi-cant form to the reduction of CO2 emissions to the atmosphere and to energy savings and efficiency.
They have the ability to help to obtain the commitments acquired in the occasion of the Kyoto Protocol. Therefore, it seems to invite clearly to its application like a good present solution to the pow-er and environmental problem.
The DER offers the following important advantages:
• It reduces the losses of energy in the systems of electrical transport and distribution • It reduces to the investments in new systems of transport of electrical energy
• It reduces the air emissions to the atmosphere and helps in attaining the agreements of the Kyoto Protocol, by applying renewable energies or co-generation systems.
• Favor the promise of power quality provision.
• DER provides a good tool to improve the power generation and environmental problems. • Nevertheless, the development of the DER will depend to a great extent on the legislative
input and support. In that regard it is important to consider that the liberalization of the elec-trical markets is changing the rules of these markets, with simultaneous threats and oppor-tunities for the DER.
REFERENCES
1. Gas Natural Foundation. (2003). Distributed electrical generation. Technical guides of energy and
environment.
2. Gas Natural. (2005). Distributed electrical generation. Manual of design.
3. Crespo, J.M., Bischof, K. and Beltran, M. Gas Natural. (2005). Simultaneous production of electrici-ty, heat and cold with natural gas.
4. World Alliance for Decentralized Energy (WADE). World Survey of Decentralized Energy 2005.
5. World Alliance for Decentralized Energy (WADE). World Survey of Decentralized Energy 2004.
6. World Alliance for Decentralized Energy (WADE). World Survey of Decentralized Energy 2002-2003.
7. U.S. Department of Energy. (2000). Strategy for Plan Distributed Energy Resources.
8. Arthur D. Little, Inc. (1999). Distributed Generation: Understanding the Economics.
9. Peças Lopes, J.A. Management of MicroGrids. European Project: Large Scale Integration of
Mi-cro-Generation to Low Voltage Grids - MicroGrids.
10. National Renewable Energy Laboratory (NREL). (2003). Distributed Energy Resources Intercon-nection Systems: Technology Review and Research Needs.
11. International Energy Association (IEA). (2005). Variability of wind to power and to other renewa-bles. Management options and strategies.
12. ECN, IZT, TAKES Europe, RISO National Laboratory. (2002). Decentralised Generation: Devel-opment of EU Policy. DECENT project.
13. Tatsuo Kume, Osaka Gas. (2005). Green Power in Japan & Strategy of Osaka Gas.
14. Tatsuo Kume, Osaka Gas. (2004). Gas Cogeneration Systems in Japan.
15. Hillmann, W. Ruhrgas AG (2004). CHP-Market: The current situation in Germany.
Preface
This report includes CHP case studies from a representative part of the involved IGU member coun-tries in the SG 5.4. Study Group. The objective with this task was primarily to register differences in cost for installation and operation of CHP plants in different countries, and secondly to analyze the ob-served difference. The material has been collected through 2004-2005.
The case studies were separated in three different categories, dependent of power capacity:
A: Micro installations: 1kW - 10 kW
B: Mini installation: 10 kW - 500 kW
C: Normal size installation: 500 kW - 50 MW.
Information was gathered upon the following items:
Installation name (geographical site) Installation technology Equipment Manufacture Capacity Power capacity kW Heat capacity kW Cooling capacity kW
Efficiency (related to net calorific value of natural gas)
Power efficiency % Heat efficiency % Total efficiency %
Cost for equipment and installation (in € or $)
CHP (hardware ab factory) (excl. ventilation, chimney, connection to gas supply, water system etc.)
Ventilation, chimney, connection to gas supply, water system etc. Installation costs (plumbers, engineers etc.)
Operation & Maintenance
O&M (€ or $/kWh produced electricity (excl. main overhaul and fuel)) Main overhaul cost/how often (€ or $ - each xx hours)
Running hours per year
Income for Power and heat
Delivery to public network, price per kWh electricity. Total delivery per year.
Substitution price by own consumption of produced power. Prices for heat delivery. Delivery/year.
Installation and conditions for grid connection
Standards to follow
Is interconnection to public network obliged according to law? - What are the conditions for supply to the public grid?
Public support for installation of CHP? How much? Public support to power price from CHP? How much?
Result of incoming case studies:
Received 25 case studies in total: 1 from Belgium, 2 from the Czech Republic, 7 from Croatia, 2 from Denmark, 3 from France, 3 from Germany, 3 from Japan, 2 from Slovenia, 4 from Spain
From these case studies can be drawn the following primary information:
Country Name Technology Power Ca-pacity MW Power effi-ciency % Hardware cost €/MWx1000 O&M cost € cent/kWh
Belgium Zwevegem Microturbine 0,1 30 810 1,4 Croatia Gas&Oil Comp GT 10 27,8 ? 0,59 Croatia Pharmacy Comp. GT + ST 4,9 + 1,1 30,3 ? 0,64 Croatia Gas&Oil Comp. GT 2 x 3,2 27,8 ? 0,59 Croatia Utility Zagreb GT 2 x 70 32,5 ? 0,33 Croatia Utility Zagreb GT 2 x 25 28 ? 0,5 Croatia Energy Inst GT 0,075 31,7 ? 0,88
Croatia Utility Comp. GT 2 x 25,6 28 ? 0,5 Czech Re-public Dwelling Zaleza GE 0,15 34,8 520 2 Czech Re-public Dwelling Troja GE 2x0,15 34,8 566 2 Denmark Copenhagen Airport Microturbine 0,1 30 800 1,5 Denmark Viborg KV GT + ST 42 + 16 44 1.293 0,85 France ? GT - Eurot. 0,020 28,6 680 ? France ? GE - Zanting 0,21 33,9 625 ? France ? GT - Cap-stone 0,030 26 1.660 1,5
Germany Restaurant GE - Sen-ertec 0,0053 29 2.360 3,0 Germany Hospital GE 0,45 34 755 1,0 Germany Hospital GE 10,3 32 535 0,5 Japan Kawasaki GT 6,5 29,2 615 0,84 Japan Wärtsila (Hitchi Zosen) GT 5,82 43,4 595 1,3 Japan Mitsubishi GT 0,815 40,8 610 1,9 Slovenia Business Centre, Celje 2 GE (Jen-bacher + abs. chiller) 2 x 0,521 + cooling ca-pacity 892 kW 39,1 1.500 (incl cooling ca-pacity) 0,8
Slovenia Elan, Be-gunje GE - Caterpil-lar 0,77 36,7 750 0,73 Spain El Prat de Llobregat GT (CC) 48,2 46,1 508 0,4 - 0,5
Spain Montigala Microturbine + Chiller
0,1 30 (Cooling 65%)
960 0,6
Spain Mortuary Microturbine + chiller
0,08 23 (cooling 65%)
1.250 0,6
Spain Badalona GE+ Chiller 1,8 38 (cooling 65%)
Due to many “question marks” it is quite difficult to draw more specific conclusions. As a general ob-servation can be concluded that the installation price is falling from 1 - 2 million €/MW for the micro plants to app. 0,5 million €/MW for mid size plants from 1 - 10 MW. For the O&M cost the level is 0,4 - 3,0 cent (€)/kWh.
Power efficiency for the GT’s from 25 - 30% for the micro plant and up to 46% for GT CC plants at 48 MW power capacity. For the gas engines from 29% for the micro plants up to 38% for the engines > 1 - 2 MW power capacity.
Concerning price conditions for Gas and Power the following results were observed:
Country Gas price Power Price Other specific inf.
Belgium 2,67 cent/kWh 4 cent/kWh to public
network
9 cent/kWh for own consumption
CHP certificate - 2,5 cent/kWh
Croatia 1,3 cent/kWh - 2,6
cent/kWh for small consumption (micro cogeneration)
5,9 cent/kWh
Czech Republic 1,94 - 2 cent/kWh 11,3 cent/kWh
Denmark
4,5 cent/kWh for heat production
1,8 cent/kWh for power production
5 cent/kWh to public network
7 cent/kWh for own consumption
Spain 1,3 - 1, 5 cent/kWh 5,4 - 6,7 cent/kWh Incentive in delivery
price - 10% of average price for all consumers
Germany 3,5 - 4 cent/kWh 2 - 7,61 cent/kWh Public support to power
price 2,17 – 5,11 cent/kWh
France 2,696 - 2,72 cent/kWh 9,9 - 10,574 cent/kWh CHP contracts for 12 years
Slovenia 2,4 – 3,3 cent/kWh 0 or 5,4 cent/kWh At least 75% efficiency
for sale of power to public network Gas prices range from 1,3 cent/kWh in Croatia and Spain to 4 cent/kWh in Germany (in Denmark the shown 4,5 cent/kWh is paid only for natural gas used for heat production). The gas price in most cas-es is correlated to the level of power priccas-es. However, the highcas-est power price is achievable in France and The Czech Republic, despite a quite low gas price.
The difference between gas- and power prices, that in most cases are the driving force behind the in-vestment in the CHP plant, seems optimal in France and The Czech Republic.
CASE STUDY - BELGIUM
Group B - Mini CHP (10 kW - 500 kW)
Microturbine installation at the Steam Plant Zwevegem, Belgium. A microturbine TURBEC T 100 in CHP-mode was installed in 2001/2002.This unit has been installed for 1 year next to the water boilers installation of one industrial factory. The object of the study was:
To validate under real life conditions the performances of the unit announced by the constructor
To determine the most probable applications for this cogeneration unit, based upon size, reliability, power
The heat output of the Turbec was added to the existing heat supply
This option was chosen so that the Turbec would not cause a disturbance for the heat production. The electricity was consumed on site by the client.
Conclusions
The installation has performed satisfactory from a technical point of view (power and efficiency)
CASE STUDY: GROUP B - MINI CHP (10 KW - 500 KW)
Installation name (geographical site) Steam Plant Zwevegem, Belgium
Installation technology Micro Turbine
Equipment Manufacture Turbec, Sweden
Capacity Power capacity kW 100 kW Heat capacity kW 167 kW Fuel consumption 333 kW Efficiency Power efficiency % 30 % Heat efficiency % 54 % Total efficiency % 84 %
Cost for equipment and installation (in € or $)
Cost of unit 81000 €
Installation costs (piping heating, piping gas, stack /exhaust, air
in-take,…) 65000 €
Electrical connection 18000 €
Operation & Maintenance
O&M - € or $/kWh produced electricity (excl. main overhaul) 14 €/MWh Main overhaul cost/how often
Periods between overhauls (in between) 6000 hours
Running hours per year 5700 hours
Emission
NOx at full load < 15 ppm at 15% of O2
CO2 680 gCO2 / kWh
Income for Power and heat
Delivery to public network, price per kWh electricity. Total delivery per year.
40 € /MWh Substitution price by own consumption of produced power. 90 €/MWh
Prices for heat delivery. Delivery/year. 25 €/MWh
Prices for delivery of cooling. Delivery/year -
Natural Gas price € or $/kWh. Consumption/year. 26,7 €/MWh ; 1695 MWh LVH gas
Installation and conditions for grid connection
Standards to follow Codes from Distribution Network Operator
Is interconnection to public network obliged according to law? - No - but allowed
What are the conditions for supply to the public grid? Price for the commodity
Public support for installation of CHP? How much? No
Public support to power price from CHP? How much? CHP-certificates: 25 €/MWh
Time for depreciation/used interest rate (with an availability of
95%)
