How can one Justify the extra coas of the Plug in?

Solar panels are heavily subsidized. The true cost of solar power is much higher.

Be sure to add the cost of solar panel if you want to attribute the saving from it.

 

The unsubsidized price of SunPower panels, installed with a 25 year warranty is about $25000 for 5kw. In my area you get about 1700 kwh per year per installed kw. These panels will lose 0.25% per year. Just using 25 years...even though the panels should last longer, but ignoring likely inverter replacement once (10 year warranty ) you get 212500 kwh for $25000 or 11.7 cents per kwh. 30% off for federal subsidy makes it about 8 cents.

Of course you need to add in the cost of the upfront money, subtract some for increases in rates, etc. In addition if you have time of use pricing you may be able to sell high (peak summer rates) and buy low (even charging at low night rates ).

The solar leasing business is based on the above math.

Mike

 

You also need to consider TOU options.
My excess solar is sold back at 11.3 cents/kWh.
My car charges overnight at 5.7 cents/kWh.

 

oh yea . . . . unlike nukes & carbon based fuels ...

 

Mike, nice breakdown of solar costs. Most panels now come with micro-inverters which should last the life of the panel.

With PG&E on the E6 time of use plan, I charge my PiP off-peak at 10-11 cents/kWh. Most of the electricity used in the house is also consumed at this rate. Excess electricity is then sold back during the 6 month "summer" window at over 30 cents/kWhr.

 

FWIW I installed a 5.5KW system a year and a half ago, and did it for about $15k before incentives / credits, or about $7k net. Bought a pallet of Canadian Solar panels and the Sunnyboy inverter direct from sunelec, and found a local contractor/installer willing to let me do most of the work.

Smith Family Solar 5.520kW | Monthly

 

Panel costs have dropped so much over the last 10+ years that now other factors represent more than 50% 0f the total install cost (labor, hardware, inverters, permits, etc).

Charting the Fall of Solar Prices - Kyle Thetford - The Atlantic

 

No sympathy here, I'm afraid. If I've got my calculations right, at current fx we pay just over $8 per US gallon. I'm surprised EVs and PHEVs haven't taken off more over here, though it is picking up. 2000 claims in Q1 for our plug in grant, when there have only been 8000 since it started.

 

True, but then they cost more to start with. They provide some other benefits, such as being able to handle partial shading better. But then they are also always up in the hot sun and degrade performance slightly. I'm actually shopping around right now and have heard both the various pros and cons. Actual long term performance data is hard to come by, but I welcome any specific info anyone has.

Mike

 

Oh, one other data point. For that 5 kw system, over 25 years the 212500 kwh will provide enough power for an EV to go 850K miles (@ 250 wh/mile), which is 34000 miles per year. You can cut that in half and still go 17K miles per year, which is more than the US average. (283 wh/mile would get you 15K miles/yr)
Just to put this into perspective...if you were to buy 3 average priced cars over 25 years (~$30K each right now) if you paid and extra $10K - $12K (i.e. $100K instead of $90k) you'd have free fuel for the 25 years if they all were EVs. Obviously we aren't yet to the point where a fully functional, long range capable EV is that cheap yet. But maybe in 5 - 10 years we will be, IMO.

To fuel those same 850K miles with gas, even at 50 mpg and a $6/gal price (a very low 25 yr average) would be over $100K.

Mike