Planning and Designing Active Solar Thermal Systems SEI REHEAT seminar, Inchydoney Xavier Dubuisson Senior Sustainable Design Consultant
About us Integrated Sustainable Design Consultants Multi-disciplinary team of engineers, architects and researchers Offices in Dublin and Cork Xavier Dubuisson, DWEcoCo Ltd
Why Solar Heating? 25,000 Gtoe/year 800 Gtoe 9 Gtoe
Key market drivers General awareness Peak oil, climate change, renewables Building Regs (Part L 2007): 10 kwh/m2,year Or 1500 kwh/year for average house Or approx 3.5 m2 of solar water heating SEI Grants: Greener Homes Scheme REHEAT programme Keep up with the Jones s
Fast growing market Ireland: +200% growth in 2008 or c. 45,000 m2 c.75,000 m2 in operation Europe (27): +60% in 2008 or 4.76 million m2 40,000 FT jobs
Climax Solar-W ater Heater, patented in 1891. Bayley s thermosyphon solar water heaters c. 1915
Solar irradiation, kwh/day,m2 horiz, January Solar irradiation, kwh/day,m2 horiz, July
Solar Trajectory Equinox 90 - latitude = 37 in Dublin Summer solstice 90 - latitude + 23 = 60 in Dublin Winter solstice 90 - latitude - 23 = 14 in Dublin Solar Resources - Solar Radiation 2-3 Xavier Dubuisson, DWEcoCo Ltd
Components Forced Circulation
Source: www.solarheymark.org
Simple collector rating warm Calpak VTN Range Apricus AP Solar MK Greenline AKT 0 Solari Panda Navitron SFB Star Consol DS-22-47-1500 UK Westfa VRK Thermomax Solamax rvel Kloben CPC Diffusion C DMK Viessmann Vitosol tosol Paradigma CPC ol pollo un Dalpex DT 1 1 Ritter CPC WK K Solar UK Lazer 2 c Thermomax MS a Quattro 2000 Thermomax MS nny line O Solar Thermomax Solamax ine Paradigma CPC ugl Thermomax Mazdon Viesmann Vitosol FK SchücoSol Schott ETC ol tosol tosol Thermomax Mazdon O Solar 0 100 200 300 kwh/m2yr 400 500 600 0 100 200 300 400 500 600 700 kwh/m2/yr = A*[G* h0 - a1*(tcol-ta) - a2*(tcol-ta)²] Qcol,annual = Σ (Qcol)+ A : Aperture collector area m² Qcol
3-24
Small/medium system layouts
Large solar systems layouts
Closed Drainback System Drain-back level 10 litre Drainback level Boiler, Windo w, or other obstacle s Source: Zen Renewables Robust frost protection of the collector and piping Overheating protection of the system Durability No risk of chemical pollution of DHW But constraints on pipework route
Solar air systems
Orientation, inclination, shading and layout of collectors Annual percentage solar insolation (%) North West East Angle of inclination Exam ple South Exam ple: 30 / 45 South-w est = 95 % Height Xavier Dubuisson, DWEcoCo Ltd Distance 4-6 x height
DHW demand & solar fraction Law of diminishing return!
SWH sizing A: Single-family SWH B: Large SWH Source: Viessmann Solar cylinder: Vs = 40-50 litres/person Typically for twin-coil cylinder: 1.5-2 x daily hot water demand
Over dimensioning leads to overheating problems Energy Space heating demand Standard dwelling Low energy dwelling Enlarged solar system Hot water demand Solar system jan feb mrt apr mei jun jul Loss due to overcapacity Source: ZEN Renewables aug sep okt nov dec
Online tools & software http://www.valentin.de/ calculation/thermal/start/en
Roof integrated Source: Solaris Source: Schuco Source: Carey Glass Solar
On-roof Progressive Solar Ltd Source: Progressive Solar Source: Viessmann Ned Forde Ltd
Flat roof installation Rosette to prevent w ater dripping into the house Bituminous felt roof Feed and Return of the collector Source: Zen Renewables Source: Shüco Source: Zen Renewables construction Sensor cable protection pipe
Façade mounted Source: Shüco Source: Conness
Ground mounted Source: Kedco Source: Conness Source: Conness
Planning exemptions - solar Domestic Commercial Max. aperture area 12 m2 50 m2 Distance between plane of roof or wall & panel Max. 15 cm 1m Max. height of panel above ground (free standing) 2m 2m Distance from the edge of wall or roof Min. 50 cm 50 cm Min remaining open space around the building 25 m2 n.a.
Life-Cycle Analysis Costs: Investment: Up to 10 m2: 700-1000 euro per m2 Bet. 10 m2 and 50 m2: 600-800 euro per m2 > 50 m2: 500-750 euro/m2 Maintenance: 0.5-1% per year Revenue: Energy substituted: Oil: 0.06/kWh LPG: 0.08/kWh Natural gas: 0.32/kWh Electricity: 0.19/kWh (day) and.10/kwh (night) C02 tax: 30/tCO2
Example DHW demand = 73 x 30 l/pers = c.2200 l/day @ 60 C High efficiency solar flat plate collectors, south facing, 40 tilt 50 m2 aperture 2500 l. Vs 80 m2 aperture 4000 l. Vs Capital cost 37,500 57,000 SEI grant 11,250 17,100 Net cost (installed) 26,250 39,900 Solar fraction 45% 60% +15% Specific yield 550kWh/m2 450 kwh/m2-20% IRR 13% 10% Year to positive CF 10 12 NPV 38,000 45,000 +50% +20%
Discounted Cash Flow 50 m2
Discounted Cash Flow 80 m2
Accelerated Capital Allowance Budget 2009 (consultation till 3 April 09) 100% of the capital cost of eligible equipment in the first year of purchase (equal 12.5% subsidy)
Training workshops In partnership with Nicer Training: Micro-generation Systems Solar Thermal Systems (23 October, Cork) Energy Retrofitting of Houses Passive House Design See www.nicertraining.ie for details & full programme
Solar Without Frontiers www.solarwithoutfrontiers.com
Get in touch: Cork Office: The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the Universe to do." Galileo Galilei 1st floor Lawley House, Monahan Road, Co Cork T: 021/496 6757 F: 021/496 6771 Email: xdubuisson@dwme.ie