If/when solar becomes big enough so that it overwhelms the grid during the day, like I said earlier, we can easily shift charging to daytime from night. There are a lot of industrial loads that run at night to take advantage of low off-peak rates that I'm sure would prefer to run during the day as well.

Low interest loans are available that let you take advantage of solar with low money up front - you can easily roll the cost into your home loan.

At some point we will have enough solar so that storage is required, but by then costs are projected to be low enough to make it worth while regardless.

Solar will likely be a dominant energy source in the future as costs fall unless something better comes along. But still, it will be far from the only source of energy. My primary point is that solar today can provide energy for less than the cost of gas for the most efficient car on the market - and it takes a lot less solar PV than one might expect.

Getting enough solar PV so that grid storage is required to make use of it is not going to happen overnight.

By the time you get to that point you'll have enough used EV batteries from old EVs to use for static grid storage for load shifting and the cost of solar PV will decline even further. The rest of the time, you'll plug in at work to charge instead of plugging in at home.

Solar PV will never be the sole energy source except in localized areas. It will always be more cost effective to use some other source of energy to get the rest of the way without a ton of storage, but instead of fossil fuels and all the drawbacks that come with burning those, perhaps it will be methane captured from landfill, sewage treatment plants, etc (not to mention whatever other renewables make sense in the area such as wind, geothermal, etc).

Done!

Assuming 3 kWh / mi (less efficiency than your number) and driving 12,000 mi year for a consumption of 4,000 kWh / year.

In Phoenix, Arizona (one of the sunniest areas of the USA, 1 kW of solar PV will generate about 1600 kWh / year (data from PVWatts)
In Seattle, Washington (one of the least sunny areas of the USA, 1 kW of solar PV will generate about 1000 kWh / year.

So in Seattle you need about 4 kW of solar PV and in Phoenix you need about 2.5 kW of solar PV. Solar PV is only around $4 / W or less for a residential install (without tax credits rebates or other subsidies) and will last at least 20 years. So for 20 years of driving or 240,000 miles, your energy will cost between $10,000-$16,000, or about $0.04-$0.07 / mile which is cheaper or equal to the cost of fueling a 50 mpg Prius!

Conclusion: Driving on solar power is possible today and cheaper than gasoline!

Very informative. I know you've done power loss testing on other drives as well. Do you have a list of drives and whether or not they passed?

Has anyone done a proper power loss corruption test on the Crucial M500? At about half the price per GB of the Intel S3500, it's a great deal, but not if the power-loss caps it has don't actually work.

Yeah, they are called micro-inverters. They convert the 25-40V DC from each panel into 240V AC (or 208V if on 3-phase) in a small box at the panel. Then you run 240VAC down from the roof into your utility panel.

When grid goes away (like when a firefighter flips the main circuit breaker or pulls the meter), the only electricity you have left is 25-50VDC at each solar panel which isn't going to hurt anyone.

Peak demand varies depending on the time of year.

In the winter, peak is around 7-8pm.

In the summer, peak is around 3-4pm. Note that "solar noon" in the summer is actually around 1pm thanks to daylight savings, not 12pm.

Solar doesn't help at all with peak shaving in the winter, but it does help a lot in the summer. Peak grid demand is always in the summer due to air conditioning load.

Again, depends highly on the time of year and weather conditions. But yes, some grid storage would be very effective at eliminating more of the peak, but it wouldn't take much, just enough to shift a small portion of the generation a couple hours later.

Very cool way of detecting circuit impedance. I guess the trick will be figuring out at what point do you say "hey, the resistance is changing too much, let's just slow down some amount" or "hey, the resistance is changing too much, I better shut down immediately".

This also depends on Tesla being able to accurately control exactly how much current is being pulled as well.

The real trick is distinguishing short term fluctuations that are caused by a flaky connection from some short term fluctuations caused by other big applicance turning on and off (you know, like an electric range/oven/water-heater/air-conditioner/pool-pump/etc)...

Arc-Fault-Detection may pick up some of the failure modes that lead to these issues, but when you are pulling 240V/40A to charge the car (9600W) It wouldn't take much of an issue to melt down a receptacle. And it won't pick up a high resistance connection in an outlet. A 3V drop in a small area (120W) probably more than enough to burn up a receptacle in the time it takes to charge the car but would otherwise be completely normal in most charging situations.

The proper fix here is to install a thermoswitch in the plug that triggers either a significant reduction in charge current, or shuts down charging completely.

You never see 208V measured from hot-hot in homes unless you have severe voltage sag - only 240V single phase with 120V measured from each hot to ground.

208V is commonly seen in commercial 3-phase situations, though, where you tap 2 out of 3 hots and each hot is 120V measured to ground.

Your typical house runs on 240V single phase power fed by two hots and a neutral.

Each hot is 120V, but shifted 180* out of phase, so you get 240V measured across both hots. The neutral handles any imbalance in power draw across the two hots.

Your typical household appliance runs on a single hot split phase at 120V and current is returned on the neutral line.

There's really no reason why we couldn't start using 240V directly these days and eliminate the neutral as long as all your appliances are able to run on 240V instead of 120V. Most modern electronics will run on both without issue.

NEC defines a continuous load as one that can run for 3+ hours.

The reason you are supposed to derate continuous loads is because the circuit breaker is likely to trip under those conditions. Not necessarily that it would be likely to cause a fire.

This is key and it is important to determine exactly where this fire occurred.

The Tesla supplied UMC is designed to adapt to multiple plug types with an adapter so one can plug into a NEMA 14-50 (typical stove outlet), 5-15 (standard 120V outlet) or others.

It is well documented that these adapters can melt - it appears that in some conditions the adapter's PINs do not establish a good connection leading to overheating. Here are three examples:

http://www.teslamotorsclub.com/showthread.php/15304-Plug-Adapter-on-my-Universal-Mobile-Connector-has-melted
http://www.teslamotorsclub.com/showthread.php/18092-Schmelted-UMC-NEMA-14-50
http://www.teslamotorsclub.com/showthread.php/23212-Scary-issue-with-Nema-14-50-adapter-melting

Now that doesn't mean that's what happened here. Faulty 14-50 outlets (no fault of Tesla) have also caused similar issues. There are two examples in this thread:

http://www.teslamotorsclub.com/showthread.php/19576-Burned-220V-Adapter

If it were me, I would not be using the Tesla UMC (Universal Mobile Connector) for daily charging - these plugs/outlets are not designed for daily plugging/unplugging. I would use the Tesla HPWC (High Power Wall Connector) instead and save the UMC for actual mobile use.

I am also not crazy about the design of the adapter plugs on the UMC. Not only do the pins appear not to necessarily mate very well (compare these pins to the connector that actually plugs into the car!), but the extra length of the adapter exerts extra leverage on the outlet/adapter which makes it easier to end up with a poor connection unless you support the UMC well.

NEC says that for continuous loads, you can pull up to 80% of the circuit's rating. Charging an EV qualifies as a continuous load. Below is a list of common copper wire sizes found in your typical home and it's 100% / 80% ampacity (assuming 60C rated insulation which is most common):

14AWG: 15/12A
12AWG: 20/16A
10AWG: 30/24A
8AWG: 40/32A
6AWG: 55/44A
1AWG: 110/88A

Note that for the last two, you typically would be using that wire on a 50A or 100A circuit, the max continuous loads on those would be 40A or 80A respectively.

Your typical plug for charging a Tesla Model S would be a NEMA 14-50 outlet rated at 50A. You might be able to find 75C rated outlets/wire, in which case one can use 8AWG wire for a 50A circuit instead of 6AWG.