No energy source is free. The cost is in extracting it and efficiency has a very narrow definition in engineering and does not include cost.
Sent from my iPhone > On Jul 18, 2019, at 10:33 AM, Lee Hart via EV <ev@lists.evdl.org> wrote: > > Mark Abramowitz via EV wrote: >> Is solar thermal water heating *still* more efficient? > > "Efficient" has a different meaning when your energy source is free. Energy > efficiency usually means getting the most good out of a finite source of > energy. > > Suppose you have a limited roof area that can only collect 1 KWH of energy. > PV cells might convert that into 150 watts of electricity. A solar water heat > might convert it into 300 watts of heat in your water heater. Which is more > useful to you? > > But most roofs are so large that the amount of solar energy available is > "limitless". You're limited more by what you can spend, and what appearance > dictates. PV is more popular than thermal because it's cheaper. The > efficiency is less, but you make up for it with more panels. > > It's like the "ICE" solution wins. When you treat oil supplies as > "limitless", then extremely inefficient ICEs are the popular choice, because > it's cheaper. > > -- > In software development, there are two kinds of error: Conceptual > errors, implementation errors, and off-by-one errors. (anonymous) > -- > Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA) > _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
