Showing my power bill from the local utility and what I’m using/spending for grid electricity now vs. this time last year when I didn’t have the solar PV system. My grid usage since installing the PV system last fall has been cut almost in half consistently every month (for context, I’m a single guy living on my own so a 2-3 kW system would be more than enough for what I need – a typical family would need at least a 4 kW system or bigger). I paid approx. $1000 for the materials to build the panels (‘diy’ is just more convenient for me – but homeowner’s can buy professionally manufactured and certified panels in bulk for between $0.40-$0.70 per watt). Another $300 for controllers, $500 for the inverter and $1800 for the battery bank (enough storage to last approx 12 hrs before dropping to 50% capacity which is the recommended limit for getting the longest life out of a battery bank – that means needing twice as much batteries, but it also means replacement every 8-10 years instead of every 2-3 years). That’s around $3600, plus a couple hundred more for wiring, connectors etc. so I would say I’ve invested close to $4000 total into the off-grid PV system. By saving just $40-50 every month on grid power, it could pay for itself in 6-8 years and last twice as long again after doing so and yield a 150%+ NET return – that makes it a profitable investment, not just a moral gesture, and grid-tie PV systems can be done a lot more affordably still. I averaged quite a bit more in savings per month last winter compared to the previous though ($100+/month), because I had the 14 kBtu solar thermal system for daytime backup heat instead of using electric or wood. More Info about that can be found at my website: http://www.resystech.com
Post time: Jun-30-2017