Solar homes and the FFE.

Hi All,

Just wanted to open up a thread for those that are interested in learning more about home solar "grid tie" and "off grid" setups and
how they relate to charging your car.

who else here is driving their FFE on sunshine?

I've gone solar, but it isn't cost effective for everyone. I use about 300KWhs/mo to charge the car, which pushes up the cost of all my other power use because it puts my cost per KWh in the upper teirs. I'm in So Cal, so I have Edison, and can end up paying quite a bit for power if I use a lot. If you pay near $0.10 per KWh, then solar isn't going to pay for itself any time soon.

Batteries isn't worth it if you have access to the grid. Batteries wear out and need replacement every so often. Consider "the grid" a maintenance free battery. Another thing to consider is that if you use batteries, you will need a larger solar system. Reason is, you would need enough generation to supply your power in the short days of winter. For "grid tie", the power company should credit you for over generation in the summer which can be used in the winter. And then there are the days where the clouds are out and raining...or a solar eclipse...you would need a generator too.

Anyway, for me, it is fun to generate what I use....but it comes at a cost.

Hi David,

what is the size of your system in kWh?

Mine is about 7 kWh... at the peak of summer can do about 45 KWh a day. so far, haven't had an electrical bill in 3 years and have a
bunch of net meter credits - I'm curious to see over time how this works out as I intentionally overbuilt my system to try and offset 100% of my annual kWh usage... adding about 10% on top to account for an EV. Also went with DWP's "Time of Use" on a dedicated 240V circuit... That should save some money as the utility charges a cheaper rate for EVs on TOU meters.

looking forward to the day when we can draw power from our cars to power our house in an emergency ;]

robochimp said:

...looking forward to the day when we can draw power from our cars to power our house in an emergency.]

Click to expand...

I am, too, but, my understanding is that we will never be able to do that with our current FFEs. Ford has stated that the V2H (Vehicle-to-Home) capability will only be practical for cars that have fast-DC-charging capability built into them, which Ford seems to be planning to do, with future model years of the FFE, but not until at least the 2015 model.

Since I live in the small town of Corning, in upstate New York, trading in my FFE for a newer, fast-DC-charging-capable, model, just to have V2H capability, is definitely not worth the expense.

...which means that my only practical option for emergency backup electrical power would be a fossil-fuel-powered generator. ...which is disappointing, since I have, otherwise, been very successful in getting the fossil-fuel monkey off my back.

I've had a 5.4-kW (pole-mounted) PV system operating for 4 years, now. We just hit the 20,000 kWh mark, for the lifetime of our system. That means that it has produced 5000 kWh/year, which has been more than enough to cover all of our electricity use, and, with the FFE we bought, in February of this year, we will probably now be pretty close to breaking even, each year.

i David,

what is the size of your system in kWh?

Click to expand...

Sorry for the late reply. My system is just under 5kw and would probably produce up to 30kwhs per day peak in summer. At this time of year, I'm seeing 25kwhs in a day...when it isn't cloudy outside...funny, I used to love rainy days. I am also doing TOU EV. I get credited over 3x for extra power generated during the day vs what I charge the car at during the night. Last months bill gave me a credit of $50, however this month is struggling due to some cloudy and raining days...my bill is currently projected to be $4.

So far, I'm very happy with the performance.