My electricity is only about 10 ¢ kwh in Arizona from 8pm to 3pm. Only on peak for five hours. Im still considering a small solar system just to charge the car. Any advise on this?
I did a ton of research on solar (retired, so plenty of time) before I took the plunge. I would be happy to go over the technical details that are much too numerous to post. PM me and I’ll give you my phone # if you’re interested.
Short list of non technical points:
1 Get estimates from every reputable solar installer in your area and play them off each other just as you do when car shopping. This will save a lot.
2 Get every thing in writing; especially warranties and power production estimates. Most use Aurora software to estimate production over a calendar year. So you can compare not just $/installed kW, but also $/production. Just be sure the production estimates you’re comparing use the same software calculations so it’s apples to apples for the return on investment.
3 Talk to and visit if possible past clients to weed out problematic companies.
4 Compare warranties of different manufacturer’s solar cells; both product and efficiency to see which panels are more cost effective.
For example, I went with Panasonic panels which were
-almost as efficient as pricier ones
-had lower yearly loss of efficiency
-have a 25 yr product (malfunction) warranty, not just an efficiency warranty
5 After due diligence and agreeing to price and specifics, then ask for extras at time of signing the contract. (If you ask for them up front they will just fold them into the total price). Again just like car buying. For example, for no price increase I got my monitoring hard Ethernet wired to my router instead of WIFi, an extended manufacturer’s warranty on the inverter, and a 5 year labor warranty.
Now my entire system is warranted for 25 years Parts and 5 years labor, and the solar panels have a 25 year production warranty (some are only 20).
6 Only technical note to mention since you’re in Arizona which implies plenty of heat to go with all that sun, is to check the thermal coefficients of the panels because efficiency declines with heat at different rates for different PV panels. (Kinda of like cold reducing efficiency in our EVs, just in the opposite direction.)
7 It’s cheaper to do it all at once rather than go small and add to later.
8 Some manufacturers now have inverters with built in EVSEs. I don’t know how much they increase the price but if you don’t already have a Level 2 EVSE it might be worth checking into.
9 South facing panels with no shade and net metering maximize efficiency and reduce the time needed to break even. Check local utility to see how long you’re grandfathered in for net metering since utilities are trying to do away with this. This is crucial for ROI calculations.
Best wishes and feel free to PM me for more details.