Project summary. Sperwerflat I Sliedrecht Netherlands

Transcription

1 Project summary The social housing association Tablis Wonen realised a 90 m 2 collective solar thermal system for hot tap water production on an appartment complex with 80 flats. The project took place as part of an overall renovation of the hot water installations. Small individual gas-fired kitchen tap water heaters that emitted exhaust gases into the dwellings have been replaced by a central solar hot water system. There are several benefits for the tenants: hot water comfort has been improved, indoor air quality has been improved, problems with moulds have been solved. The collective solar energy system provides in about 35 % of the hot water demand. The solar system compensates the increased energy consumption due to central hot water circulation and higher water consumption (increased comfort). Building Type of building Multi family house Number of users/dwellings, floors 80 dwellings 10 floors Year of construction 1968 Total effective area (heated) 8,746 m 2 Hot tap water consumption 1,784 m 3 /a, (measured/estimated) Whole energy consumption for heating 110,298 kwh/a purpose after CSTS implementation System engineering Year of construction of CSTS 2003 Type of collectors Flat plate collectors Thermal power 62.3 kw therm Aperture area of collectors *) 89 m 2 Buffer storage./. m 3 Hot tap water storage 3 m 3 Total capacity of boilers with energy source 687 kw, natural gas Type of hot tap water heating Type of heating system Costs Total cost solar system 50,211 Euro Cost of CSTS / gross area of collectors 564 Euro/m 2 Subsidies 31 % Output Output of solar heat **) 39,900 kwh/a Reduction of final energy ***) 57,000 kwh/a CO 2 -emissions avoided 10.5 t CO 2 /a Solar performance guarantee A.L. Bijkerk, Head real estate: The integral retrofitting of the Sperwer building with a central solar hot water system resulted in a lot of wins for the tenants: Better comfort, better indoor air quality, lowered indoor humidity, savings on the energy bill and a contribution to climate change mitigation. Since this project 8 other buildings have been equipped with a similar central solar hot water system. Owner Tablis Wonen (Social Housing Association) A.L. Bijkerk P.O. Box AC, The Phone: Fax: info@tabliswonen.nl Operator Tablis Wonen P.O. Box AC, The Phone: Fax: info@tabliswonen.nl *) Aperture area = light transmitting area of the front glass **) measured, between storage and piping to taps (solar system output) ***) related to the measured output mentioned before

2 Technical description Hydraulic scheme not available Description of the CSTS Year of construction of CSTS 2003 Thermal power 62.3 kw therm. Gross area of collectors n. a. m 2 Aperture area of collectors 89 m 2 Type of collectors Flat plate collectors Type of assembly On flat roof Orientation of collectors South ( ) Inclination angle to horizon n. a. Freezing protection Drain back Overheating protection Drain back Operation mode High flow Use of CSTS for Hot tap water heating Buffer storage./. m 3 Hot tap water storage 3 m³ Control of backup-system/csts Separated control: The control cares for a temperature difference between collector and storage of 10 K. The collector pump will be switched off at a temperature difference of 2 K.

3 Technical description (2) Hot tap water system Type of hot water heating Recirculation system For decentralised systems:./. The installation on the consumer site Size of storage for hot tap water 1 m 3 Specification./. Summary The solar hot water system consists of a 90 sqm collector surface and a storage volume of 3,000 litres. Solar collectors and storage are seperated by a plate heat exchanger. Solar heat is stored in tap water. Space heating system Type of heating system Number of boilers 2 Total capacity (power output) of boilers 687 kw Capacity of each boiler and the year of construction. 1: 470 kw (1995). 2: 217 kw (1995) Energy source Standard (.1) Type of boiler system Condensing (.2) Type of operation Operator of the CSTS system CSTS monitoring Data accessible via internet Scientific monitoring & follow up Maintenance contract Visualisation of the solar heat output Yield of CSTS plant Output of solar heat Measuring point Reduction of final energy Solar performance guarantee Self operation : Solar radiation, Output of solar heat, Total water & Hot water consumption; Comparison of input and output (once a year) : 39,900 kwh/a Measured Between storage and piping to taps 57,000 kwh/a Monitoring (meter readings) Heat consumption Whole energy consumption for heating 110,298 kwh/a purposes after CSTS implementation Measured Energy used for Hot tap water heating Whole energy consumption for heating n. a kwh/a purposes before CSTS implementation Total tap water consumption 6,800 m 3 /a Hot tap water consumption 1,784 m 3 /a, Hot tap water temperature 65 C Cold water temperature C Planner GTI Utiliteit P.O. Box DB Barendrecht, The Phone: Fax: Installer see Planner Producer ITHO P.O. Box AA Schiedam, The Phone: Fax: info@itho.nl

4 Financing & Investment Introduction: The turn-key system delivery cost amounted to 564 /m 2 (total 50,000 ) paid for by the owner/investor Tablis Wonen. Subsidies have been granted form three sources for in total 31 % of the cost. Financing of CSTS Form of financing Purchase 69 % self financing Distribution in percentage 31 % Costs of solar materials Total cost of solar system Detailed costs for Collectors Elevation/mounting structure Storage/heat exchanger Backup heater Control Installation Planning/Engineering Others Operation costs of heating system Power cost for pumping Maintenance cost Monitoring cost Other operaton cost Total operation cost Or: Increase of operation cost after CSTS implementation 50,211 Euro /a /a /a /a /a /a The subsidy is a mix of three items: Contribution from the project Ruimte voor zonnewarmte (Space for Solar) Energy Performance Regulation (national programme to support RE and EE) Subsidy of the energy utility Eneco Addresses Stichting Platform Ruimte voor zonne-energie (PLUS subsidy of national Energy Performance Regulation PLUS subsidy of Energy Utility company) Frank Zegers P.O. Box RK Utrecht 3503 RK Utrecht, The Phone: Fax: F.Zegers@ecofys.nl

5 Development & Experiences Quantitative aspects of the CSTS Installing solar thermal systems fit in the social responsibility policy goals of Tablis. Specifically for these flats the hotwater system has been renovated to improve living conditions (no exhaust gases in the flats, less moist and moulds) and comfort (improved hot water comfort). In order to compensate for the related increase in energy consumption (due to central circulation and increased comfort) the solar systems were added. Summary of experiences / tices to the project performance Initially Tablis was interested in the implementation of heat pumps. This was not possible due to difficult technical integration. For this reason, a solar thermal system appeared to give similar environmental opportunities, that fitted in the policy of the housing association. A feasibility study carried out by Ecofys turned the lights on green. Afterwards we got a turnkey offer from GTI based on Space for Solar tender. Once subsidies were secured, building permit and consent of tenants were obtained, to decide on Go or no go was easy. We were using the home installer instead of the installer promoted by the Space for Solar project. May be this was more expensive but it saved a lot of negotiation/discussion time due to the existing close working relations. The net costs for our tenants did not increase, while the comfort and indoor air quality have improved significantly. The residents of the appartments are very happy with the new solar hot water supply of the Sperwerflat. We only received responses that were full of praise. Many housing corporations are looking for an acceptable alternative of individual hot tap water heaters. This collective solar hot water system is an alternative that will (at least at our association) get followups. Experiences management Experience problems or failures? Find solutions to these problems or failures? Addresses Financial effects/project performance Project economically efficient?, not in terms of return on investment; investments are only partly recurred from the tenants; on a net base the tenants do not pay more; Tablis bears the uneconomic part of the investment costs Fiscal or other financial effects? Effects on rental fees? Experiences technical staff Experience problems or failures? Find solutions to these problems or failures?