10-20-2012, 04:51 AM
1. Chinese solar panels are available for $1/W locally (Hilo). I find it hard to believe that the inverters/mounting hardware really add $2.5/W.
2. Specs from Rolls say you should avoid more than 3 parallel sets in your battery bank. "No parallel connections" makes sense from an engineering perspective, but as with everything it's really a price/performance tradeoff -- eliminating all parallel connections means bigger/more expensive batteries are necessary to achieve any real capacity.
My opinion: grid-tie is a scam since you're still beholden to HELCO. Replacing batteries every few years is still cheaper than the minimum HELCO fees. For that matter, grid power here is so expensive that gas generators are cost-competitive....
2. Specs from Rolls say you should avoid more than 3 parallel sets in your battery bank. "No parallel connections" makes sense from an engineering perspective, but as with everything it's really a price/performance tradeoff -- eliminating all parallel connections means bigger/more expensive batteries are necessary to achieve any real capacity.
My opinion: grid-tie is a scam since you're still beholden to HELCO. Replacing batteries every few years is still cheaper than the minimum HELCO fees. For that matter, grid power here is so expensive that gas generators are cost-competitive....