One may only have a $25 electricity bill, and if that's true, then you're doing very well with your house's efficiency!
But another thing to think about is your car! If you switched to an electric car (or EV for Electric Vehicle), you would need to charge it. And if you install Solar Panels, you could be driving a Solar Powered Car. Now, wouldn't that be cool?!

Tax Credits

You get $7,500 federal tax credits (but no NM state tax credits) if you purchase a new EV.
But there are no tax credits for used EVs, leased EVs, or converted EVs. And restrictions exist on the number of cars sold. Credits phase out after 200,000 cars are sold by the manufacture (thus buying a Tesla Model 3 in a few years may not qualify, but you can always talk to your legislature to get the law changed, and credits extended!)
For more information: www.fueleconomy.gov/feg/taxevb.shtml or see the IRS page.

Questions to Ask Yourself

  • Do you do mostly city driving?
    If so, an EV is a great idea! 
    With gasoline cars, the MPG is better with highway driving than with city driving. 
    However, with EVs, the equivalent, MPGe, is better in the city, thanks to the battery getting recharged when breaking.
  • Do you drive long distances at a time?
    If so, an EV might not make sense until their range (i.e. how many miles before having to re-charge) is longer.
  • Is there a charging station where you work? Is your workplace amenable to installing one or many charging stations?
    If so, this might make your commute very attractive, as work would partially pay for your "fuel"!
  • Do I like filling up my car and taking it in for oil changes?
    If so, keep the gas car! If not so much, then consider an EV. EVs have much lower maintenance! No engine oil to change (ever), no gears to strip, no transmission fluid to worry about, and no gas to fill. Electric motors are direct drive, so the entire engine is gone, simplified to a no gear/ no clutch electric motor (or between 1 and 4 motors depending on the car).

Comparison of the 2016 & 2017 EVs

Below is a list of the 2016 and 2017 EV models available. It contains information on price (MSRP in $), battery, range in miles, amount of kWh used for city (c) and highway (h) driving, Mile Per Gallon equivalent (MPGe) for city (c) and highway (h) driving, horsepower of the engine and full charging time of the battery.

To open this table bigger in an another window, simply click on it.


This table will be updated as more information becomes available.

The information regarding MPGe and kWh per 100 miles can be found at:
Information regarding battery charging can be found at: 

Converting your Gasoline Car into an Electric Car

Turning your gas vehicle into an electric vehicle costs between $12,000 and $20,000 depending on the performance and the range desired, plus 120-200 hours of labor.

The range is limited by space, weight, and cost. For most city users, a daily range of 40 mile seems like a good number. 

Just like an engine which has a limited lifetime in miles, usually of the order of 200,000 - 300,000 miles, the battery of an EV also has a life expectancy, which rather than being a function of miles, is a function of charge cycles and depth of charge.

Since the LiFePO4 battery technology is supposed to yield 3,000 - 5,000 charge cycles, as long as:
  • the depth of discharge doesn't go too deep too often;
  • the batteries remain 'balanced' without any cells over-voltage at end of charges.
One can get an expected life expectancy of the battery of:
  • 60,000 - 100,000 miles for a 20-mile battery range;
  • 75,000 - 125,000 miles for a 25-mile battery range;
  • 150,000 - 250,000 miles for a 50-mile battery range.  
As for replacing the battery and displacing of the old one, it depends on the battery chemistry. LiFePO4 batteries are mostly copper and aluminum foil. Li is non-toxic, so many recycling facility will accept them. However, the Prius' Ni battery is toxic and the recycling of such battery is much more difficult.

How Much Electricity will your Car Use?

Depending on the EV, and depending on the driving you do (mostly city, mostly highway, a mix of both), you'll use more or less kWh.

From the summary table above:
  • for city driving, the range of energy (kWh) usage is 25 to 39 kWh per 100 miles.
  • for highway driving, the range of energy (kWh) usage is 30 to 41 kWh per 100 miles.
For the purpose of our calculations, let's use 34 kWh per 100 miles
Note that at $0.09 a kWh, that's ~$3/100 miles. This turns out to be ~3 times cheaper than buying gasoline: at $2.5/gallon and 25 miles per gallon, that's ~$10/100 miles.

And so, even if rooftop solar does not work for you, going to an electric car makes financial sense, as well as ecological sense, since it avoids the exorbitant pollution caused by fracking and transporting oil to gas stations.

To figure out the electricity your car will use, you need to find out how many miles you drive in a week, in a month and in a year?
  • For someone commuting to work ~20 mi/day, or ~100 mi/week, or ~5,200 mi/year, the yearly car electricity consumption would be ~1,750 kWh/year.
  • For someone commuting to work ~55 mi/day, or ~275 mi/week, or ~14,300 mi/year, the yearly car electricity consumption would be ~5,000 kWh/year.
  • For someone commuting to work ~90 mi/day, or ~450 mi/week, or ~23,400 mi/year, the yearly car electricity consumption would be ~8,000 kWh/year.
This calculation is interesting as it shows that commuting to work 55 mi/day uses about as much electricity as our house exampleusing on average 405 kWh/month!

Powering your EV with Solar Panels

In our house example, for a house using 5,000 kWh/year, the approximate system size is 5,000/(0.8*2,100) = 2.97 kW and the number of panels was 9.1.
To add the required kWh for 5,200 mi/year, you're looking at ~1,750 kWh/year, a system size of 1.04 kW, and 3.18 panels.
To add the required kWh for 23,400 mi/year, you're looking at ~8,000 kWh/year, a system size of 4.76 kW, and 14.55 panels.

So the system for your house and for your car could be ~12 panels or ~24 panels.

You can Wait to Buy an EV, but you could Take Advantage of the Tax Credits for Solar NOW, and Bank your kWh for later!

If you can't get an electric car now, you can add extra solar panels to your system and purchase an EV later, as currently, PNM will accumulate (roll over/bank) your kWh rather than buying them from you. This way, you'll be able to plug an EV later and using up your accumulated kWh.

What's the Carbon Footprint of EVs?

Cleaner Cars from Cradle to Grave (2015, Union of Concerned Scientists)Over their lifetime, battery electric vehicles produce far less global warming pollution than their gasoline counterparts—and they’re getting cleaner.

Electric cars have lower carbon emissionsOver the lifetime of each vehicle (about 160 thousand miles), a gasoline vehicle will emit about 75 tons of greenhouse gases, while most EVs in Minnesota will result in only 29 tons, and many will result in only 3.4 tons of GHGs (from vehicle manufacturing).