Advances in Building Integrated Photovoltaic Technology 2

1. BIPV Design Considerations

2. Environmental Factors • Insolation available • Climate & weather conditions • High ambient temperature will reduce PV output • Local atmospherics such as cloud can impact • Pollution of any form can require cleaning • Shading • Latitude (affecting optimal angle of PV panels)

8. Prof. Michael Wallis,Loughborough University • “What we are saying that if you have the solar panels facing east-west then you can even out the power during the day. You may lose about 10 per cent of power if you go east-west but this addresses a problem that exists in Germany where because everything is facing south, you get this peak power at midday which is very difficult for the grid to cope with. • “So in Germany they are advising people to go east-west so they are smoothing out the supply of power from all these solar panels. We get similar spikes of power too, although it wouldn’t make sense for people to change their solar panels if they have already been installed. • “In total we have 2.8 Gigawatts of solar in the UK but Germany has approaching 20 Gigawatts. In Cornwall they can’t install any more solar panels because the grid can't handle it.”

9. BIPV Building Technologies

10. Bifacial PV Cells • Cells encapsulated within glass, allowing light to be captured from both sides of the cell. • This improves the efficiency of the cell. • Bifacial cells are prized for their aesthetic properties, and are often used on canopies of shades. • They are useful architecturally as they allow some light through to the area below, but also provide shading. • Bifacial cells offer a 25-80% energy power advantage1 over monofacial cells. 1.http://www.nrel.gov/technologytransfer/pdfs/igf20_gamma.pdf

11. Glass PV roof • Using the glass PV panel itself to form the surface of the roof

12. Glass PV roof Striking when used in large areas

13. PV Skylights Range of interesting ‘transparent’ thin film and organic technology trajectories. Onyxsolar.com

14. PV Skylights cont. • These can be installed as the skylight glass itself • An alternative is as an additional layer over the skylight itself. This has the added bonus of ease of maintenance/repair and added insulation and cooling • PV’s can either be: • Opaque, with clear glazing between adjacent cells allowing light through. • Semi-transparent – DSC technologies and suchlike, which allow some light through. • Newer technologies promise “see through” photovoltaics, which attenuate the light, but allow for clear vision.

15. PV Canopy gepower.com

16. PV Canopy • One of the simplest installations Gaining popularity in warmer climes where shading of parking is often normal • Visibly promotes charging of cars (if a charging point is fitted) and gives visitors an early indicator of company ethics Silicon Based Bifacial Cell onyxsolar.com

17. Dye Sensitised / Semi Transparent

18. PV Building Façade • Designed as a façade that generates energy as well as performing as a façade • In this example, the manufacturer (ruukki.com) provides a complete mounting system with studs, flashings, fasteners and electrical components. There are no visible cables and no wall penetration for the electrical install (easier to install and maintain)

19. PV Building Façade cont. EWE Arena Oldenburg, colt 2009 M9 ARCHITEKTEN Senfter + Lanzinger Schott Solar

20. PV Building Façade cont. • As on the previous page, the façade can be used to provide shading to the occupants • Shading can be constant, intermittent, fixed or movable, such as these examples of brisesoleil • ertex-solar.at

21. Retrofit can be used to improve the quality of the built environment. • Many buildings with system built concrete / exposed finishes. Structurally sound, but exterior facades suffer from spalling. • PV offers an attractive solution.

22. Price of façade materials (2011) • Figures based on Odersun products and are Euro per m2

23. Brise Soleil • This is not a picture of a solar installation. • These are plain old boring Brise Soleil! • BUT, illustrates an interesting point. • City centre school in Nimes (France) • Unintended consequences • Kids use as a climbing frame!

24. Spandrels and Parapets • Spandrels are part of the exterior wall of a building (between the floor and the bottom edge of the window). • Parapets are waist-high barriers at the edge of balconies, bridges, etc. Semitransparent PV modules integrated into spandrels/parapets can obscure the view of the inside, while allowing a free view of the outside. • Structurally, they have the properties of laminated glass and can be used to create attractive accents on the façade (solarfassade.info)

25. Spandrels syracuseglass.com archpaper.com bisem-usa.com

26. Parapets / Balconys solarbuildingtech.com kolumbus.fi

27. Solar PV Rooftops • The standard rooftop mounting available: • Parallel to roof • Angled mount imetco.com asera.net

28. Solar Roof Slates Images courtesy: Solar Century • C21 Solar slates. • Integrate with cost-effective concrete tile system • Low visual impact, aesthetically pleasing.

29. Solar shingle • Dow are marketing solar integrated shingles in the US under the name Powerhouse

30. Thin film roof PV • Flexible thin film modules laminated to a roof membrane • Lower efficiency than rigid, but more flexible in location altenergymag.com

31. Direct mount PV • By tweaking the design of regular PV panels, a direct mount that negates many mounting problems / wind load etc lumetasolar.com

32. Direct mount PV • If this mode of PV deployment were to be included in the design phase, savings could be made • Roof load would be lower reducing requirement • Elimination of fixtures, removing cost and speeding build • Less wind load issues as PV is flush to the roof

33. Direct mount PV • Including the PV as part of the sawtooth / northlight design. Alignment complements both aspects. solarfassade.info

34. Who do you need to involve for a successful design? • BIPV manufacturer • Architect • Project manager • Structural engineer • Electrical engineer • Building shell designer • Façade / roof contractor Opportunity for firms offering an approach that holistically integrates professions and trades.

35. What other functions could BIPV perform? • Privacy screening • Solar protection • Architectural design element • Heating • Thermal insulation • Weather protection • Residual structural support • Burglary protection (toughened glass) • Sound protection and insulation

36. Conclusion • There is a global future for BIPV • It is growing • It will remain focused upon the primary areas of façade, roof, spandrels, parapets and balconies • Increasing energy efficiency and carbon reduction measures will drive demand, as will improved PV efficiency AND innovation in the field • Success will come from the integration of the BIPV into the construction process and the building itself, so a partnership with façade / roof manufacturers and/or those providing the mounting systems would seem optimal

37. If you found any of this interesting… Please stay in touch Gavin Harper g.harper@glyndwr.ac.uk www.gavindharper.com http://www.cser.org.uk/ https://www.westproject.org.uk/ @gavindjharper @CSER_PV @LCRI_WEST