On 22 Sep 2015 at 15:12, Robert Bruninga via EV wrote: > People forget that battery systems are not only very inefficient ...
Doesn't that depend on how you use them? For example, lead batteries are very close to 100% efficient between 0% and 80% SOC. Virtually all of the energy goes into the charging reaction and almost none into heat. I suspect that other chemistries have similar SOC ranges over which they're similarly efficient. > ... require maintenance ... Most modern batteries don't need the kind of maintenance required for lead, no? > but whenever they are fully charged, then the solar panels are > providing nothing in return for their investment. Oh, there I agree! It's a major challenge and expense to provide enough capacity to store all the energy a big PV system harvests in a day, especially if you don't need it within the following 24 hours. If you have nowhere to go in that dump-pack-charged EV, you're going to need a LOT of storage to hang on to the energy. So that infinitely large battery, the grid, is great to have. Trouble is, it's not free to use, and you (we) don't own it. Because most utilities are privately owned businesses, we the public have no fundamental right to access that big battery. But business controls politics, and the laws that once controlled these regulated monopolies and granted us that right are rapidly being ground down. The grid is apt to get a lot more expensive to use, if not unavailable, in the years ahead. So while I think you're right about the grid in the short term, I suspect that the long-term future for storing solar energy for your EV is in batteries -- LOTS of them. The idea of using depreciated lithium EV batteries whose diminished capacity no longer serves for the EVs is really appealing, as long as it doesn't mean lowered efficiency. (Reduce, reuse, recycle ...) David Roden - Akron, Ohio, USA EVDL Administrator = = = = = = = = = = = = = = = = = = = = = = = = = = = = = EVDL Information: http://www.evdl.org/help/ = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Note: mail sent to "evpost" and "etpost" addresses will not reach me. To send a private message, please obtain my email address from the webpage http://www.evdl.org/help/ . = = = = = = = = = = = = = = = = = = = = = = = = = = = = = _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
