4 U SE CASE : TU/ E S CIENCE P ARK As a case study, the technical feasibility of using geothermal energy for TU/e Science Park (the
4.3 Future and trends
In the future, the energy demand of the TU/e Science Park will change. This is caused by changes in the use of the campus itself and by external factors like the changing climate. As the changing energy demand will influence the feasibility of geothermal energy on campus, projections are made for the period 2010‐2050. These projections are based on available data from the university real estate management department. 4.3.1 The campus Over the years, the use of the campus has changed considerably. With respect to the energy use of the campus, not only the number of buildings has increased, but also the building quality has improved, centralised heating has been replaced by the ATES and local heating systems, other functions are housed on campus and ambitions/goals have changed. Short term (2020)
In its latest plans, named Campus 2020, the university plans to have renovated approximately 120,000m² of the oldest buildings and demolished 20,000 m², by the year 2020. Figure 25 shows the extent of the changes planned in this project. All new or renovated buildings will be connected to the ATES and will not be connected to the gas grid. A significant reduction in energy use is to be expected because the total amount of gross floor area will be reduced, the average building quality of the campus will be significantly increased and the energy supply efficiency will be increased because of the use of the ATES. The ambition of the university for the year 2020 is to have reduced their own annual electricity demand to 30,000,000 kWhe
(excluding third parties). Both the reduction in electricity use by the university and an expected increase of third party floor area, will contribute to an increase in the share of third party electricity use in the total.
4.3 Future and trends
Figure 25: A birds‐eye view of the campus as seen from the West, with all planned changes for the future indicated in white, as described in the campus master plan.
The numbers indicate the phases in the Campus 2020 project.
The gas use of the university is expected to decrease in the future as well. This expectation is based on the fact that more buildings will use the ATES for heating and cooling energy supply. The gas use of third parties on campus is expected to remain constant. The ambition of the university for the year 2020, is to have reduced the campus annual gas use to 3,500,000 m³. The heating and cooling load covered by the ATES is expected to have doubled by that time.
In a meeting with the university real estate management department at 29 November 2013, it was indicated that the option to use power from a biomass fed combined heating and power plant (CHP) from the municipality, is being investigated. This CHP is intended to provide sustainable heat to the ‘Strijp S’ area, a hospital and a retirement home, all North of the campus. This hospital and retirement home could also be connected to the campus ATES, decreasing the heat surplus of the campus. This CHP plant could provide the TU/e Science Park with 2 MWe of base load power. The department is also investigating the use of photovoltaic
cells, to cover part of the campus’ peak load.
Long term (2050)
The long‐term ambition of the university is described in the document ‘Naar de City of Tomorrow’ from 2012. In these plans, the university states the ambition to ‘Practice what you teach/preach’. Because one of the main themes of education is ‘sustainability’, the university wants to become an example of sustainability and make the campus a showcase of the research and education housed on it. For instance, the university is one of the world’s leading institutions on the subject of solar cells, and this should be visible from the outside. The ultimate goal of the university in this perspective is to generate all the energy demand on site. As a first step towards this goal, the first targets are to have reduced the energy use by 50 % and to be 50 % self‐ sustaining in the year 2030.
4.3.2 External factors
Several factors contributing to a changing energy demand of the campus, are not (fully) controlled by the university itself. Among these external factors:
Climate change; in their report on climate change from 2007, the Intergovernmental Panel on Climate Change state that an increase in the global average temperature of 2‐3°C is to be expected by 2050. Also, cold days, cold nights and frosts are very likely to become less frequent, and heat waves are likely to become more frequent [42]. These changes are likely to increase the cooling demand of the campus while the heating demand is decreased.
Policies; changing government policies can change the required/chosen energy strategy of the campus. With the built environment accounting for 40 % of the primary energy demand, it is likely that building performance requirements will become stricter.
User behaviour; users have a large effect on the energy demand on campus. This could simply be because of a change in the number of users on campus, but also the way the campus is used. For instance, although partly influenced by the university itself, changes/trends in the (inter)national educational systems can cause changes in the use of buildings e.g. video lectures causing less student to come to the lectures, and the use of computers increasing the building’s cooling load. Another example is the recent trend in the use of electric cars that can be charged on campus. Third parties; as mentioned before, third parties are responsible for approximately 20 % of the campus energy use. The influence of the university on their energy use is limited. Of course, governmental policies also apply to these parties, which could change their demand.
4.3.3 Other sustainable energy sources
For a sustainable future electricity supply to the campus, a combination of sources is assumed to be likely. Apart from geothermal energy, both photovoltaic and biomass power are considered in the energy supply variants, to account for the influence of interdependence between sustainable sources. Please note that the following projections are only applicable in certain scenarios (see §4.4).
For the projection of the electricity supply from the CHP plant, it is assumed that 2 MWe of
electrical power from the CHP is available at any time. For the increase in installed PV capacity between 2010 and 2050, the proposed profile from ‘Naar de City of Tomorrow’ is used [43]. For the years 2030‐2050, the total surface area is assumed to remain constant.
Figure 26 shows a graph of future conversion efficiencies for different types of solar cells, as projected by the International Energy Agency [44]. Based on this graph the conversion efficiency of the solar cells on campus is assumed for the respective periods in which the panels are installed.
4.3 Future and trends
Figure 26: Projected development of PV conversion efficiencies until 2030.
The resulting projection of the development of the total surface area, the average conversion efficiency and average power of the PV‐cells installed on campus is shown in Table 7. The average power is based on an average irradiation of 1,000 kWh. Table 7: The projected development of the total surface area of PV‐cells installed on campus 2010 2013 2015 2020 2030 2050 Increase in surface area [m²] 0 1,000 4,000 10,000 20,000 0 with efficiency ‐ 20% 21% 23% 25% ‐ Total PV surface area [m²] 0 1,000 5,000 15,000 35,000 35,000 Weighed average efficiency ‐ 20 % 20.8 % 22.3 % 23.8 % 26 %* Annual average power [kWe] 0 22.8 118.7 381.8 950.9 1,038.8 * Additional increase because early panels will need replacing in this period Linear interpolation is used to determine the annual average power projections for the intervening years. The yearly variation of the available power is represented using a cosine function. The amount of annual variation is characterised by an assumed constant, defined by the average PV power (winter), divided by the average maximum PV power (summer). This constant is assumed to be 0.15. The following formula is used to describe the projected instantaneous PV electricity supply:
( )
( ) 1
1
cos
2
1
8760*3600
pv annualt
P t
P
t
(39) With: Pannual Projected average annual electricity supply [kWhe] α Ratio of Pmin/Pmax (=0.15) [‐] In Figure 27, this formula is illustrated for the 2010‐2050 period.
Figure 27: The projected PV electricity supply for the TU/e Science Park.