Potentials for ground-mounted Solar District Heating for small towns in Europe

Transcription

1 Potentials for ground-mounted Solar District Heating for small towns in Europe Svensk Solenergi SOLVÄRMEDAG Kungsbacka Christian Kok Skov Project manager

2 History Idea: Creating an independent consulting firm to supply competent advice concerning all forms of renewable energy and energy efficiency solutions. Established in Purpose: To promote the use of resource-saving and environment protective systems. The objective will be furthered through commercial and information activity within renewable energy, rational exploitation of energy and energy planning as well as information activities. Independent consultancy. Non-profit fund (a self governing business institution). More than 30 employees. Solvärmedag Kungsbacka Christian Kok Skov 2

3 Locations Offices in Skørping Aarhus Copenhagen Location of tasks Solvärmedag Kungsbacka Christian Kok Skov 3

4 Work areas PlanEnergi specialises in the development and creation of customised environmental solutions in renewable energy, rational energy use and energy planning. Implementation Research & Development Main work areas: Energy planning Local CHP and district heating networks Biogas planning, design, project planning and general consultancy Wind and PV planning, mapping, installation pattern and EIA with visualisations District heating based on renewable energy (solar thermal, seasonal storage, heat pumps, etc.) Solvärmedag Kungsbacka Christian Kok Skov 4

5 Background for the analysis Starting point questions: We have seen a strong SDH development in Denmark in the past decade what are the characteristics of the Danish SDH systems? Would it be possible to see a similar development in other countries? The basis for the analysis of several (!) DH networks: How much land area would be required for large-scale solar collector fields to cover a certain share of the annual DH demand? Could this land area be found near the town? Would such SDH system be considered economically reasonable, i.e. how would various cost limits reduce the potentials? Solvärmedag Kungsbacka Christian Kok Skov 5

6 Background for the analysis (2) Screening across Europe of potentials for similar SDH systems as seen in a well-established market Analysis carried out as part of the IEA SHC, Task 52 Solar Heat and Energy Economics in Urban Environments (task52.iea-shc.org) Published report: SDH Trends & Possibilities Characteristics of Ground-Mounted Systems for Screening of Land Use Requirements and Feasibility Collaboration with the Heat Roadmap Europe project ( to develop spatial analysis of area availability. The Heat Roadmap Europe project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No Solvärmedag Kungsbacka Christian Kok Skov 6

7 Development of SDH in Denmark Find solar plant data and statistics at: Solvärmedag Kungsbacka Christian Kok Skov 7

8 Why? Why this good development in Denmark? Subsidies? Only partially Optimal climate conditions? - No Tax on fossil fuels } Low production price for solar heat* Solar heat competitive to natural gas in DK * < /MWh (20 years loans and 3% interest rate) Long tradition for district heating - low distribution temperatures Small user-owned district heating companies supplying even small villages in the countryside Solvärmedag Kungsbacka Christian Kok Skov 8

9 Danish SDH trends summary The results show that the typical Danish SDH system is in the range of 5,000-15,000 m 2 ; has an annual solar collector yield of approximately 400 kwh/m 2 ; requires an investment of million financed by a long-term, low interest loan (e.g years, 2-3 % interest rate); covers 20 % of the DH demand in a relatively small town with around 4,000 inhabitants and located within 200 m of the DH network where it replaces natural gas in a CHP plant which has a diurnal storage having a volume of around 0.2 m 3 per square meter of collector installed. Solvärmedag Kungsbacka Christian Kok Skov 9

10 Typical Danish SDH plant But alternative options also exist Solvärmedag Kungsbacka Christian Kok Skov 10

11 SUNSTORE 3 40 % SF: Dronninglund Concept for increasing flexibility and renewable energy share m 2 solar thermal collectors m 3 pit thermal energy storage 2.1 MW (cooling) absorption heat pump Combined with existing bio oil boilers and natural gas CHP Solvärmedag Kungsbacka Christian Kok Skov 11

12 Dronninglund: Overview Solvärmedag Kungsbacka Christian Kok Skov 12

13 Dronninglund: Pit storage Solvärmedag Kungsbacka Christian Kok Skov 13

14 Pit Thermal Energy Storage Cheap storage technology for large volumes Floating lid with insulation No insulation to the ground Solvärmedag Kungsbacka Christian Kok Skov 14

15 Methodology Solvärmedag Kungsbacka Christian Kok Skov 15

16 Restricting the DH networks The objective has been to identify the most obvious candidate SDH cities, based on general qualifying conditions Only the DH networks without opportunity to access waste incineration ( waste-to-energy or WtE) or excess heat (e.g. from industrial processes) are included in this analysis Reason: It may not be logical to establish a SDH system in places where there is simultaneously a need to cool down a similar (or even larger) amount of excess heat. In these cases, it should be explored if it would make sense to utilise the excess heat already available. Solvärmedag Kungsbacka Christian Kok Skov 16

17 Restricting the DH networks (2) To identify relevant cities for SDH the following criteria are applied: No excess heat source within 20 km No WtE facility within 20 km Suitable land for solar collectors available in the city vicinity (distances of 200 m and 1,000 m from the city boarder investigated) The analysis does not represent the full potential for SDH in either Europe as a whole or in the individual countries! This is only a first step to identify possibilities (hence, SDHEP1 ) Think of this as a pre-feasibility study for a selected case x3,000 Solvärmedag Kungsbacka Christian Kok Skov 17

18 Restricting the DH networks Disqualifying DH with nearby WtE or excess heat means that most big cities and the majority of existing DH demand are not included Solvärmedag Kungsbacka Christian Kok Skov 18

19 Solar collector yield Global horizontal radiation for each geographical location (JRC dataset) 40 % solar utilization collector yield [kwh/m 2 ] solar radiation [kwh/m 2 ] Land-to-aperture area ratio: 3,5 m 2 /m 2 Two analysed field sizes relative to heat demand: % solar fraction % solar fraction (considering storage losses) Solvärmedag Kungsbacka Christian Kok Skov 19

20 Spatial analysis of suitable land Søllested (DK) example: DH network (yellow), agricultural land within 200 m vicinity (green) 20 % SF SDH system that was installed in 2016 (red) Solvärmedag Kungsbacka Christian Kok Skov 20

21 Spatial analysis of suitable land (2) Dronninglund (DK) example: DH network (yellow), agricultural land within 200/1000 m vicinity (green) 40 % SF SDH system that was installed in 2014 (red) incl. water pit storage for seasonal storage (blue) Solvärmedag Kungsbacka Christian Kok Skov 21

22 Suitable land located in most cases 100% 90% Potential land area as share of required area - 1,000 m 80% 70% 60% 100% 50% 40% 30% 20% 10% 0% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Potential land area as share of required area m Solvärmedag Kungsbacka Christian Kok Skov 22

23 Distribution of the land use classes Solvärmedag Kungsbacka Christian Kok Skov 23

24 Potential SDH in Sweden 255 DH networks included: 16 of these lack space 1 has enough space for 13 % SF 2 space for between 20 to 40 % 236 has enough space for 40 %! 10 TWh DH demand in total Pan-European Thermal Atlas (PETA): Solvärmedag Kungsbacka Christian Kok Skov 24

25 Assumptions for Economic Analysis No need for major refurbishments in the existing DH systems to integrate the solar system. Four investment categories are considered: 1. Solar collector field including installation, main components etc. 2. Thermal energy storage (Steel tank or Pit Storage) 3. Transmission line to the town 4. Cost of land Solvärmedag Kungsbacka Christian Kok Skov 25

26 Assumptions for Economic Analysis (2) Cost of heat is calculated for each location based on: Economy of scale (based on Danish experience): Specific investment decreases with size ( /m 2 and /m 3 ) Pump electricity included for solar collector field (3kWh el /MWh) and transmission line Heat losses incl. for storage and transmission line 3 % p.a. rate investment loan 25 years of technical lifetime and payback period Solvärmedag Kungsbacka Christian Kok Skov 26

27 Kungsbacka example Heat demand: 142 GWh/year Green areas within 1000 m vicinity: 10.5 mio. m² Horizontal solar radiation: 921 kwh/m²/year Solar fraction (to DH network) 20 % 40 % Area of collector field m² m² Ground area of collector field m² m² Share of available ground within 1000 m 2.6 % 6.5 % Storage volume m³ m³ Solar heat production 28 GWh 71 GWh Estimation of heat losses 2.7 % of solar heat 20.9 % of solar heat Estimated heat price (delivered at network) 34 (360 SEK)/MWh 53 (560 SEK)/MWh Solvärmedag Kungsbacka Christian Kok Skov 27

28 Kungsbacka example (2) DH network Non-irrigated arable land Pastures Land principally occupied by agriculture 20 % SF 40 % SF Solvärmedag Kungsbacka Christian Kok Skov 28

29 Identified solar heat potentials Status Solvärmedag Kungsbacka Christian Kok Skov 29

30 How price limits reduce the potential 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Share of total identified solar heat potential below solar heat price limit (in /MWh) Solvärmedag Kungsbacka Christian Kok Skov 30

31 Conclusions (1:2) Mainly smaller DH networks do not have excess heat/wte nearby Larger DH utilities: Investigate excess heat first? but could consider SDH - to supplement the excess heat source (depending on available quantities, supply and demand profile, and storage options) - to expand their network and cover a larger area - to avoid relying on the excess heat source (e.g. an industry which may be shut down in the coming years) Remember that this is only SDHEP1 (not the full technical potential) Solvärmedag Kungsbacka Christian Kok Skov 31

32 Conclusions (2:2) In most of the investigated countries many options for SDH at reasonable price levels have been identified also in Sweden This analysis indicates that there seem typically to be space available for the systems included in the analysis Low-hanging fruits identified Go! Sizing up the solar collector field can be an effective way to reach a low cost per m 2 of collector, which is key to achieve feasible SDH Before ruling out SDH due to space limitations, consider locations for the collector field further away than usually thought to be relevant Solar thermal and seasonal storages in intelligent combinations with other production options can improve feasibility of a decarbonized DH supply Solvärmedag Kungsbacka Christian Kok Skov 32

33 Solar heat [GWh/yr] Conclusions (2:2) In most Solar heat of the potential investigated depending countries on price many limit options for SDH at reasonable price levels have been identified This analysis indicates that there seem typically to be space available for the systems included in the analysis Low-hanging fruits identified Go! Sizing up the solar collector field can be an effective way to reach a low cost per m 2 of collector, which is key to achieve feasible SDH Before ruling out SDH due to space limitations, consider locations for 0 the collector field further away than usually thought to be relevant Solar thermal Maximum and acceptable seasonal solar storages heat price in [ /MWh] intelligent combinations with SF = 20 % SF = 40 % other production options can improve feasibility of fully RE-based DH Solvärmedag Kungsbacka Christian Kok Skov 33

34 Thank you for your attention! Christian Kok Skov Dronninglund, DK Solvärmedag Kungsbacka Christian Kok Skov 34

35 Solar collector field price Specific installation costs are low for very large collector fields Solvärmedag Kungsbacka Christian Kok Skov 35

36 Storage assumptions Tank Thermal Energy Storage (TTES) is the typical standard solution Pit Thermal Energy Storage (PTES) is cheaper for very large volumes Τ V A C 0, SF 5 % m ³ Τm ² = ቐ 0.2, 5 % < SF < 30 % 3, SF 30 % 2 % yearly heat loss 20 % yearly heat loss Solvärmedag Kungsbacka Christian Kok Skov 36

37 /ha Cost of Land Agricultural land prices Cost of land based on Eurostat data (2014). * No Eurostat data available land price estimated based on an average of Germany and Luxembourg values. ** No data available for 2014 land price projected based on data for Solvärmedag Kungsbacka Christian Kok Skov 37