Tuesday, September 20, 2016

The Future of Solar Pt 4

It is raining hard this week in Tokyo, and I have not seen the sun clearly once since I got back from a trip to the U.S. nine days ago.  Be that as it may, it is hard not to be optimistic about the future of solar, even in typhoon season. September is the month in Japan when it rains more than in the official "rainy season".

Technology and cost reduction march onward.

1. Last week, Kaneka, a Japanese company, announced a record 26.33% conversion efficiency for a "practical size" crystalline silicon solar PV cell.  Kaneka is targeting an LCOE of 14 yen/kWh in 2020 and 7 yen/kWh in 2030.  Kaneka's is a non-concentrating cell with "heterojunction technology using high-quality amorphous silicon, low resistance electrode technology, and a back-contact structure that captures more solar energy".  Nice to see Kaneka still in the game, since they are mostly known in the global industry for their earlier thin-film modules that faded when undercut dramatically by cost reductions for traditional crystalline PV modules within the past decade.

2. This is only the latest of MANY new records for cell and module efficiency this year.  Indeed, it is hard not to yawn a bit since we are so accustomed to seeing these.  The PV Magazine brief online article about Kaneka's feat also mentions or links to stories about

--Sunpower's module efficiency record of 24.1% set in June using cells from SunPower's X-Series modules.
--ZSW's 22.6% CISG thin film record from June.
--Trina's announcing in July 20.16% average efficiency for Trina's P-type multicrystalline silicon PERC cell under "industrially produced conditions" (as opposed to laboratory tests), allowing a 286w standard 60 cell module (as opposed to the 260 watt modules we were using only a year or two ago).
--Hanwha Q Cells' announcement of a 19.5% efficiency for a 72 cell module using standard multicrystalline silicon technology using its Q.UANTUM technology and four busbars.

3.  Of course, 7 yen/kWh LCOE might not be an aggressive enough target for 2030, even if 50% less than the Kaneka 2020 target.  We now see numerous PPA's in desert areas of the world for projects to be built in the 3~4 cent per kWh range.  (E.g. Peru - Enel Green Power 4.8 cents/kWh for construction in 2017, Coahuila Mexico 3.6 cents/kWh for construction in 2018, Dubai/Masdar 2.99 cents/kWh for construction 2019, and Chile, Solarpack, 2.91 cents/kWh, for construction 2019.)

Friday, September 16, 2016

... solar power takes up too much space?

This nice summary at a global level by Adair Turner notes that there is plenty of room for solar and wind power in most countries AND a low enough cost that "within 20 years many countries could get a majority of their electricity from renewable sources at an easily affordable price."  He notes that in a few countries with high population density (e.g. India, Bangladesh, S. Korea) we may need to add some nuclear and carbon recapture technologies to make a swift transition to a zero carbon economy. And some rich countries (Britain) may prefer to pay a bit more for electricity to place their wind farms offshore, for aesthetic reasons.

Japan (and Germany) are absent from the analysis.  Japan's population density (336 persons per square kilometer) is lower than S. Korea (507), India (407), Taiwan (647), Bangladesh (1119) and similar.  But like Britain Japan has a strong "NIMBY" tradition that allows localities to veto many types of developments.  So site availability will continue to be an issue for renewables in Japan.

Some ways around the issue:

Solar -- as much rooftop and BIPV as possible, on every new house and commercial or industrial structure!  Floating solar on ponds, reservoirs, etc.  Solar greenhouses.

Wind -- offshore with floating projects as they become commercially viable, and massive new capacity additions in Tohoku and Hokkaido with sufficient transmission capacity to get the power to demand centers in Kanto (and Kansai).