Starved electrolyte batteries are less prone to sulfation, but it really does happen. Because of concerns about excessive recombination, gassing and subsequent loss of life, it's my understanding that AGM batteries sulfate more in practice than they should in theory.
Well ... this is the "Solar panel systems on the grid" forum, so I wasn't even considering the "off-grid" scenario. You're absolutely right -- for off-grid applications, or environments where power outages are frequent, such as developing nations or small Caribbean islands ...
Ignoring the fact that I own a business that makes equipment capable of measuring end-to-end efficiency, with DCPV systems there are more conversion steps and often just plain more wire. They are also intermediate between ACPV / detached microinverter systems and high voltage string inverter for shade tolerance and panel mis-match.
You are wrong about FLA charge efficiency - they are very close to AGMs in "float" (on-grid ...) service, and where I see a lot of inefficiency is with the opposite of what I write up top about AGMs. Because FLAs are more tolerant of over-charging, they tend to be overcharged more. Gassing reduces charge cycle efficiency and FLA-based systems tend to be configured more towards "will gas" because the alternative is "will get sulfated". FWIW, since float service batteries are almost only ever given some kind of "daily topping off charge" the cycle efficiency doesn't apply. On account of they aren't being cycled ...
For suburban use, outside of hurricane or other severe weather areas, where power outages are very few and very far between, totally agree. I was sold on hybrid systems at a time when there was a lot of talk about energy shortages and the possibility of rolling blackouts. Developments in Demand Response have all but silenced talk about rolling blackouts. The massive deployment of wind resources (18% of current real-time generation right this moment) hasn't hurt either. Within that environment, and not living on the Gulf Coast -- hybrid systems are a waste of money. For an area like the Gulf Coast, there's no guarantee you'll have natural gas for that generator of yours. I think going with batteries is the only solution if you live in an area prone to hurricanes or whatever.
Well ... this is the "Solar panel systems on the grid" forum, so I wasn't even considering the "off-grid" scenario. You're absolutely right -- for off-grid applications, or environments where power outages are frequent, such as developing nations or small Caribbean islands ...
Ignoring the fact that I own a business that makes equipment capable of measuring end-to-end efficiency, with DCPV systems there are more conversion steps and often just plain more wire. They are also intermediate between ACPV / detached microinverter systems and high voltage string inverter for shade tolerance and panel mis-match.
You are wrong about FLA charge efficiency - they are very close to AGMs in "float" (on-grid ...) service, and where I see a lot of inefficiency is with the opposite of what I write up top about AGMs. Because FLAs are more tolerant of over-charging, they tend to be overcharged more. Gassing reduces charge cycle efficiency and FLA-based systems tend to be configured more towards "will gas" because the alternative is "will get sulfated". FWIW, since float service batteries are almost only ever given some kind of "daily topping off charge" the cycle efficiency doesn't apply. On account of they aren't being cycled ...
For suburban use, outside of hurricane or other severe weather areas, where power outages are very few and very far between, totally agree. I was sold on hybrid systems at a time when there was a lot of talk about energy shortages and the possibility of rolling blackouts. Developments in Demand Response have all but silenced talk about rolling blackouts. The massive deployment of wind resources (18% of current real-time generation right this moment) hasn't hurt either. Within that environment, and not living on the Gulf Coast -- hybrid systems are a waste of money. For an area like the Gulf Coast, there's no guarantee you'll have natural gas for that generator of yours. I think going with batteries is the only solution if you live in an area prone to hurricanes or whatever.
Comment