Rural networks, being more spread out and thus having longer cables will likely have already greater network losses and instances of voltage drop, but may well see more uptake of micro-generation; micro-CHP will be attractive to large rural homes with high heat demands as they will get more use out of it, and thus earn more money from it, though this may be mitigated by the higher price of fuel for homes not on the gas network; similarly heat pumps may be an attractive heating option for rural homes, again as homes not on the gas network will benefit more from switching from heating with high fuel costs to electric heating, and as rural homes are likely to have a larger land area which lends itself to the more effective ground source heat pumps. As for the distributionnetworks, they are likely to see greater benefits from the presence of micro-CHP, and greater problems from the presence of solar PV and heat pumps. Urban networks are likely to see lower uptake of micro-generation and what micro-generation is installed will be smaller in scale. Heat based micro- generation devices (i.e. micro-CHP and heat pumps) may be unlikely in very densely populated areas where heat networks could be a possibility, thus the impacts from micro-generation in these areas are likely to be lower. It should be kept in mind that this last paragraph has been entirely speculation on what the author expects the differences to be on other networks (plus the reasoning behind that speculation) to establish a rough hypothesis and more research will be needed to determine what the differences actually are.
Abstract. Over recent decades, there has been a growing concern about how modern technologies would impact on an electrical grid. Whilst the UK is set to meet the target of 15% energy demand from renewable sources by 2020 to ensure energy security and decarbonisation objectives, there has been a greater concern over how the increasing deployment of lowcarbon technologies (LCTs) would affect an electrical grid, in particular the residential low voltage distribution network. While LCTs can provide clean energy and decreases the dependence on oil and natural gas stocks, their impact on distributionnetworks is unknown and the operators are visibly blind as they use a ‘fit and forget’ approach. Consumers’ connections are uncertain and stochastic and the LCT uptake poses a potential threat for distribution network operators. A review is presented in this paper, illustrating the potentialimpacts the LCTs have on a local electrical grid such as voltage regulation, thermal limits, power quality and harmonics. Potential solutions, such as Deregulation, Soft Open Points, On Load Tap Changer, and Active Power Filter currently available for Distribution Network Operators and power system planners before costly network reinforcement work is undertaken.
disempowered by the multiple barriers to them taking on this new role, and instead sought to support district heating development within the boundaries of their existing powers and roles. District heating, by its nature, requires local support and coordination. This meant that the under-resourced local intermediary function within the case study was a key challenge. Re-structuring of the institutional framework is likely to require the re-distribution of resources and power from existing institutions. The case study showed some examples of how intermediaries can potentially play a role in enabling this restructuring and re-distribution of resources. For example, where local authorities had the agency to take on a new intermediary role within the energy system, they were able to work towards more radical ‘stretch and transform’ visions where heat supply was delivered through local authority-owned networks, strategically located and expanded to ensure affordable, lowcarbon heat provision (rather than privately-owned networks operating only in areas offering maximum profit margins). The nurturing activities of the local intermediaries in the case study had the potential to provide the
The rapid growth in electricity demand and retirement of existing units results in a complete redesign of the electricity generation portfolio. When carbon emissions are uncon- strained, combined-cycle natural gas plants makeup the largest portion of new capacity due to the relatively low investment cost. The capacity is deployed primarily in coastal regions to access seawater for cooling. A relatively small amount of capacity employing closed-loop freshwater cooling is also deployed in Asir: a province lacking coastlines but with a relatively high per capita availability of surface water resources. Air-cooled combined-cycle generation and combustion turbines are deployed in the remaining provinces to help support load growth without expanding transmission. Existing renewable energy policy (50 GW of installed capacity by 2040) results in wind, geothermal, solar PV, and CSP expansion. The CSP capacity is deployed in coastal regions due to the accessibility of seawater for cooling. Rural areas combine diesel generators with PV capacity to meet the stagnating demand growth anticipated under the SSP2 urbanization scenario. The constraint on groundwater withdrawals in the reference case to remain at or below 2010 levels results in an increase in wastewater recycling and desalination capacity, and expansion of the water conveyance infrastructure beyond 2010 levels is needed to transport desalinated water inland.
Currently, DHN are supplied predominantly by large-scale centralised fossil fuel heat stations. However, in future, a shift towards decentralised heat generation from low-temperature and sustainable heat sources should become a more feasible option. As a result, opportunities for prosumer participation, where homeowners can be both buyers and sellers of heat, will become more prevalent. For the prosumer concept to work, the discordance of low-temperature renewable energy supply and domestic demand must be balanced. One solution is thermal energy storage or a combination of thermal and battery storage in multi-vector energy systems (MES).
shares of ICEV + HEV will be reduced greatly from what they are today. Though this is desirable, as we wish to reduce emissions, our ethical framework dictated that the most vulnerable (in terms of mobility) require protection. Even if it is assumed that such a significant change in purchase habits in just over a decade is realistic, it is unlikely that LCV attributes will have improved sufficiently to equal ICEV, particularly in terms of costs. Under this assumption, those segments who have most reliance on car ownership will be most impacted, as they may be priced out from owning a vehicle suiting their needs or bear high costs because of their needs by the introduction of these policies, and thus could qualify for protection from the negative impacts on mobility which are indicated within the model. Further to this, the model suggests that significant downsizing may occur without necessarily providing cost savings. This has ethical implications for those customers who may require a larger vehicle (eg larger families).
CNTs play distinct roles in the different scenarios where they are exposed to high temperatures. In the applications using CNTs as flame retardants, the CNTs are expected to form a protective network and impede the fire. In incineration plants, the ideal outcome is to decompose CNTs [14, 102] and to avoid exposure of CNTs to human. In recovery operations, the temperature needs to be high enough to burn off the polymer matrix but below the point where the CNTs are oxidized. The temperature dependence of the CNT’s oxidative stability is obviously critical. The temperature in an accidental fire is not controllable. Using the more thermally stable CNTs in the retardant applications befits the “safe by design” concept. The temperatures in incineration and recovery operations should be set according to the goals. Differ- ent types of CNTs have different diameters and defects, thus variable thermal properties. The fact that the CNTs are embedded in the polymer matrix and interaction of CNTs with the molten matrix further complicate the situation. In case the CNTs and their agglomerates are liberated from the matrix, their mobility and transporta- tion may be complex in the flue gas and thermal plume . More studies for the thermal behavior of differ- ent types of CNT composites are needed to address the topic. Harper et al.  considered the release of CNTs from waste incineration to be low given CNTs can be combusted; even if the CNTs survive the incineration, they may end up in bottom ash or fly ash captured by the filters, and eventually in the landfill.
Abstract— This research describes the measurement and study of temperature in welded components using a microcontroller based temperature measurement system with Type-K thermocouple sensor. The experimentation was conducted on lowcarbon steel plates on a semi-automatic MIG welding machine using bead on plate welding technique by varying welding parameters like wire feed rate and welding speed. The temperature response was recorded for different distances from the weld bead and time-temperature graphs were plotted.
the same every time. Until furnace temperature reached 800 degrees and the heating basically completed, the tiles no longer release carbon monoxide. So the carbon monoxide concentration inside the furnace gradually stabilized. Figure 4 presents the concentration of carbon dioxide. Carbon dioxide was the most stable gas whose con- centration changed regularly. Before closing the door, the concentration of carbon dioxide was the same with that in the air. When the door was closed, its concentration increased rapidly, until occupied 5% - 6% of the total gas, then this value was fluctuating around. The value should be the one that the environment inside catalytic combustion burner reached stable.
In previous studies, many researchers examined the effects of field experimental warming on C, N and P dynamics in grassland ecosystems. However, no consistent results have been presented so far. Some studies showed that warming did not affect soil organic carbon (OC), total N (TN), and total P (TP) contents (Wang et al. 2014, Yu et al. 2014, Zhang et al. 2015, 2016), whereas other studies found that warming significantly decreased soil OC, TN and TP contents (Li et al. 2011, Rui et al. 2012, Alatalo et al. 2017). Both biotic (e.g., veg- etation biomass, microbial activity) and abiotic factors (e.g., soil moisture, elevational gradient) were considered to contribute to the contradic- tory findings (Wang et al. 2014, Yu et al. 2014).
Low-temperature radiant floor heating uses the low temperature water as the heat medium, and its heat coils are buried in the floor of building. It’s a heating mode that uses the mechanical circulating hot water to heat the room. It is comfortable, healthy, energy-saving, clean and easy to be decorated. Gradually it has attracted people’s attention, and it’s recognized as the ideal heating way at home and abroad. With the continuous development of floor heating technology, the relevant research is also developing. Many scholars at home and abroad have got a series of achievements in the theoretical and experimental aspects. S.Sattari and B.Farhanieh analyzed the effect of design parameters of floor heating on thermal performance, and they concluded that the floor layer material and the thickness have biggest effect on thermal performance. South Korea's Gook-Sup Song had do some research that the influence of change of the floor thickness and supply water temperature on the surface temperature through the experiment measurement.Zhou Xinghong had done the numerical simulation about low-temperature floor radiant heating and concluded some laws about heating. These could provide theoretical basis for design, construction and operation of heating system. Zhao Leilei analyzed heat transfer performance of low-temperature radiant floor heating comprehensively. In Yanshan University, Dong Wei and Wu Lei, had done the research and about new control strategy and temperature controller of low-temperature radiant floor heating respectively[6,7]. Xiao Yongquan simplified the average surface temperature, non-radiative average surface temperature. He established a single-valued function whose total costs is the supply and return water temperature difference and determined the optimum supply and return water temperature difference eventually. These studies had an important significance for the further development of radiant floor heating. This article mainly introduces the design and other problem of radiant floor heating system. The system uses the condensing boiler as the heating resource and the experimental heating room is faced the south in Shanghai. Through the experimental methods, the surface and air temperature distribution have been analyzed in the condition of different supply water temperature in a typical heating season. Also the supply water temperature that makes people more comfortable is obtained.
Contrary to the original focus of the stakeholder management literature on dyadic relationships between the organisation and its shareholders, a growing body of scholars (Calton and Payne, 2003; Frankforter and Hill, 2008; Frooman, 1999; Frooman and Murrell, 2005; Roloff, 2008; Rowley, 1997; Savage et al, 2008) are considering extended notions of stakeholder networks. Rowley (1997) argues that a network perspective on stakeholder relationships allows us to explore how the patterns of relationships in a stakeholder environment influence an organisation’s behaviour. He draws attention to two characteristic of organisational networks, density and centrality; and he highlights the way they affect relational dynamics within the network. Increasing network density is associated with increasing variety and intensity (e.g. Oliver, 1991). Rowley (1997) argues that there are two main consequences of dense networks – efficient communication, and the establishment of shared behavioural expectations. These affect the relationship between the focal organisation and its stakeholder network. The focal organisation has less power to resist pressures from stakeholders. In this paper, we explore these ideas in the context of the transition to a lowcarbon economy in a number of key industry sectors in the UK.
Installation of VFD’s on the condenser water pumps will allow the speed of the pumps to be varied in response to changes in the cooling loads. Since the power demand of the condenser water pump motor varies approximately to the second power with speed, (due to the fixed minimum lift conditions of an atmospheric cooling tower, the savings does not correspond to a cubic relationship) reducing the speed to 70% when the chiller load is around 70% will result in a condenser water pump energy savings of approximately 50%. At low loads, reducing the speed to 50% when the chiller load is around 50% or less will result in a condenser water pump energy savings of approximately 75%. We typically do not recommend taking the condenser water pump speed down below approximately 50%, as the savings are minimal below that level, and we need to pay attention to the minimum allowable flow rate over the cooling towers, which is typically in the 50% of design flow range.
The heating system model incorporates various controllers that dictate its operation. The heat pump is subject to on/off control with a 4 o C dead band which attempts to maintain the air temperature in the living room between and 19- 23 o C; for a second group of simulations, the dead band set points were altered to 21-25 o C. There is also a hot water precedence control within the heating system model: if the hot water tank temperature is below its set point of 45 o C, heat is diverted to it in preference to the radiators (this is a common configuration for heating systems in the UK). The heat pump also features an internal safety control that switches the device off if return water temperatures breach a user-defined set point of 55 o C: in a real unit, this prevents component failures due to excessively high pressures in the heat pump’s refrigerant loop.
Despite the proliferation of decision-making tools in recent years, tool ‘ non-use ’ is common (Radaelli 2004; Nilsson et al. 2008; Gibson et al. 2017). There are a variety of reasons for this. For example, in the energy field, tools are often focused on techno-eco- nomic criteria, yet the motivations of many policy makers extend beyond simple eco- nomic or carbon reduction drivers, to include wider social considerations such as fuel poverty, tackling deprivation and job creation (Bush, Bale, and Taylor 2016; Gibson et al. 2017). Similarly, tools may be too complicated to be used directly by the actors who need them and appear as a ‘ black box. ’ This can lead to decision makers having a lack of trust or understanding of the tools ’ outputs (Nilsson et al. 2008; Rogers et al. 2015; Kolkman et al. 2016). Conversely, where tools are used, they might be applied in politically motivated ways, to support the existing beliefs or agendas of the actors employing them (Radaelli 2004; Nilsson et al. 2008).
The pipe bending process involves a local induction heater, radial arm, rapid cooling using a water cooling device, and continuous feeding by a pusher and guider roller; our setup is shown in Fig. 1. 4) The pipe material was lowcarbon steel (SA106Gr-B) having the chemical compositions of 0.3C, 0.29Mn, 0.4Cr, and 0.4Cu (mass%). Table 1 shows the mechanical properties and chemical compositions of SA106Gr-B. In the pipe bending process, it is very important to control the pipe thickness to ensure its good performance. The thinning ratio should be <5% when the outer diameter, pipe thickness, and bending radius are 170, 11.0, and 253 mm (1.5D), respectively. Our aim is to investigate the mechanical properties to verify the applicability of bent pipes with non- uniform thicknesses. In particular, in this study, the fatigue endurance limits of the bent sections were compared with those of the raw material. The reasons for changes in the fatigue characteristics were investigated by examining the microstructure, hardness, and residual stress distribution of the bent pipe. Figure 2(a) shows the extracting directions of the test pieces in both tensile and fatigue tests, while Fig. 2(b) shows a sub-sized high cycle fatigue test specimen.
Despite some criticisms, expanded on below, our review has revealed many projects that, on the basis of the evidence they have published, appear to have been well run and have made significant strides forward in the current state of knowledge. The collective position of the DNOs with respect to innovation when the LCNF was introduced should be kept in mind [2, 6]. They had very little recent experience of specifying and managing the kind of research and development (R&D) or demonstration activities required to address the uncertainties inherent in innovation. We are confident that they have much better capability now with respect to R,D&D and its reporting than they did at the beginning. In addition to the knowledge gained within each of the themes we have identified, we believe that this, in itself, is a major success of the LCNF. The stated objective of the LCNF was to help DNOs understand how they provide security of supply at value for money and facilitate transition to the lowcarbon economy . The LCNF Governance arrangements state that projects should focus on the trialling of: new equipment (more specifically, that unproven in GB), novel arrangements or applications of existing equipment, novel operational practices, or novel commercial arrangements . Tier 1 projects were specifically required to have a Technology Readiness Level 39 (TRL) between 5 and 8. TRL 9 was excluded, as projects with this TRL were thought to be too low risk and offer limited scope for new knowledge to be generated. TRLs were not specifically mentioned in the governance for Tier 2 projects. However, the requirements for Tier 2 projects stated that projects should be neither at the R&D stage nor involve the widespread deployment of proven technology or practices. Instead, the guidance stated that methods being trialled should be “untested at the scale and circumstance in which the DNO wishes it to be deployed and that consequently new learning will result from the project”. Since the adopted definition of TRLs defines R&D as TRLs 1-5, this guidance implies Tier 2 projects should be at TRL 6 or above, i.e. demonstration and early deployment.
prominence, climate change. A civil service review of the department from 2009 declared, ‘The Department of Energy and Climate Change (DECC) was created in October 2008 to take the lead across government for tackling climate change and securing clean, safe and affordable energy for the UK. The Department’s mission is global change on a historic scale. Its role is to lead this change’ (Civil Service, 2009). DECC’s lowcarbon transition plan was published in 2009 (DECC, 2009), showing a ‘roadmap’ broken down by sector and technology, towards achieving the both the EU 2020 renewables targets and the first three carbon budgets set out by the Committee on Climate Change, under the provisions of the Climate Change Act. More broadly, since the 2003 Energy White Paper (DTI, 2003) a debate had been emerging around the institutional arrangements required for delivering on the UK’s ambitions for cutting carbon emissions by 2050(SDC, 2006a, SDC, 2006b, Lockwood et al., 2007). In order to improve the investment climate for renewables, banding of the Renewable Obligation certificates had been undertaken to improve returns for higher cost renewables at an earlier stage of development (Carbon Trust, 2006). Now however, more profound market changes were also being discussed, and Ofgem’s Project Discovery presented a series of institutional arrangements which spanned the spectrum from minimal to high government intervention (Ofgem, 2010b). With the UK’s carbon targets now set into law by the 2008 Climate Change Act (HM Parliament, 2008), there was increasing acceptance in the possibility of a stronger intervention in electricity markets being justified. Thus, in 2009, Dieter Helm observed, ‘As the replacement cycle bites in the next decade, and given the scale of the expenditure on wind, there are considerable doubts as to whether the privatised industry structure, with liberalisation and competition, is up to the task. A return to greater state intervention is almost inevitable’ (Helm, 2009).
There was no doubt that the LAs themselves would lead the actor-networks. This might be seen as surprising given the LAs acceptance that they did not represent a credible authority in relation to HNs, sitting outside the 'invisible college'. And, whilst it is true that LAs have traditionally driven municipal HN development, this is no longer an inevitability. Nevertheless, LAs were perceived by government to be the right organisations to lead the projects due to their (supposed) authority over planning, local knowledge, social and environmental aims, ability to appeal to a range of actors and to act as an 'honest broker' (Heat and the City, 2011; Wedawatta and Ingirige, 2014; Pielke, 2007). For these reasons, it is argued by Heat and the City (2011) that LAs do need to participate in actor-networks aiming to develop HNs but are not necessarily best placed to lead them, and that different organisational arrangements may be required at different points in the project development cycle.
It takes less time ti realise the net and this operation is less invasive. This means less inconveniences for citizens. The cold district heating doesn’t need a big central district power plant. This means that we have no local pollution coming from the district power plant. Furthermore at least the 70% of the energy come from a clean and renewable resourse.