Post by thread:[TECH] Solar Fuel Machine (for hydrogen) and Cree

According to the BBC website a Swiss university has produced a prototype solar machine that uses cerium oxide as a catalyst to provide oxygen as the cerium cools down during the night. The prototype production is pathetic at 0.7 -> 0.8% efficiency, they hope to increase it to 19% which they think would be marvellous (I think that still sounds pretty poor). <http://www.bbc.co.uk/news/science-environment-12051167> Elektor report that Cree have announced their CXA20 LED array which produces 1K lumens at 11 watts (I haven't read the whole article, so assume this is input power). <www.elektor.com/news/led-array-delivers-record-1050-lumens-at-11-wa tts.1649039.lynkx?utm_source=UK&utm_medium=email&utm_campaign=news> Colin -- cdb, 3/07/2009 -- spam_OUTcolinTakeThisOuTbtech-online.co.uk

> According to the BBC website a Swiss university has produced a prototype > solar machine that uses cerium oxide as a catalyst to provide oxygen as the > cerium cools down during the night. The prototype production is pathetic at > 0.7 -> 0.8% efficiency, they hope to increase it to 19% which they think > would be marvellous (I think that still sounds pretty poor). 19% is above what you can typically buy Si PV at at present. Higher exists. Max theoretical Si single junction is about 28% afair. Whether 1% is useful depends greatly on cost per area. As a parallel example eg if you had a solar PV cloth which was about free and which could be attached to house roofs for about free then at 1% a 1000 ft^2 roof would make about 100W. Not very useful by most standards. But very much so in some circumstances. > <http://www.bbc.co.uk/news/science-environment-12051167> > Elektor report that Cree have announced their CXA20 LED array which > produces 1K lumens at 11 watts (I haven't read the whole article, so assume > this is input power). > > <www.elektor.com/news/led-array-delivers-record-1050-lumens-at-11-wa > tts.1649039.lynkx?utm_source=UK&utm_medium=email&utm_campaign=news> LED sounds good, but Cree do better than that already. XLamp ML-E guarantees 1000 lumen at 10 Watt. Better l/W at lower W

On 24/12/2010 08:13, cdb wrote: > According to the BBC website a Swiss university has produced a prototype > solar machine that uses cerium oxide as a catalyst to provide oxygen as the > cerium cools down during the night. The prototype production is pathetic at > 0.7 -> 0.8% efficiency, they hope to increase it to 19% which they think > would be marvellous (I think that still sounds pretty poor). 19% is good compared to PV cells, maybe poor compared to water heating panels