I agree that what you are talking about here is a value decision, and I support people choosing electric vehicles. I disagree with people who say "a lease is not a loan, so don't worry." In fact, saying it is a rental agreement is worse than a loan. With a loan you have equity when it is paid off, with a rental agreement you have nothing.
You say it costs you $150 a month to have this car. That number is meaningless. How *long* is that term for? What are you actually paying?
If Nissan is giving monthly terms of $200 for a Leaf - great, how long is the term, and how much do you owe at the end if you want to keep the car. A four year lease is pretty typical, so four years at $200 month has you paying $9600. That means you've paid ten grand to rent a car for four years, and once those four years are up, you can either give the car back and have *nothing* to show for your $10k, or you can buy out the lease for the remainder of what the car cost ($35k after government kick backs), which puts you on the block for $25000. Only this time, you don't qualify for new car 0% rates, and instead have to pay 7% 'used car loan' rates. At $200/month it'll take you another 20 years to pay off that car. Thankfully, no one will give you a 20 auto loan.
Here's a personal example, I currently leasie a subaru wrx - not MMM approved. I have it on lease, not because I couldn't afford to buy it on loan but because the math was smarter than financing. To understand this you need to understand how leases work. In a lease I buy the right to drive the car for four years, after those four years, the car belongs to the dealership. Upon completion of the lease, I can either return the car to the dealership and have nothing, or I can buy it from them. How much do I buy it from them for? However much the original sale price of the car was, minus what I've paid to them (minus loan costs).
So, how does the dealership figure out what my monthly lease rate will be? After all, if I only pay $5/month over my four years I'll have only paid $240, and there is no way they'll be able to sell that 4 year old car for $240 less than it was worth when brand new. The dealerships have a very good idea of what a car will be worth used in four years. So, they set your lease-rate such that when the lease is up, you owe 'wholesale' on that car.
Here's the real life example. I purchased my WRX for $35k. Subaru knows that the wholesale value of a 4 year old WRX is approximately $17k. Thus, over the course of four years, I have to pay off $18k (plus taxes, admin fees, loan interest, stuff like that). So, the dealership cuts me a four year loan for $22k ($18k car value + taxes other stuff – down payment). Interest rates at the time when I got the car were 4% (anything below 3% today is subsidized by the manufacturer, and they don’t bother subsidizing cars that sell well without the extra incentive). So I am paying 4% annual interest on my $22k loan.
If I had financed the car, I would be paying 4% interest on the full $39k loan. So I’m saving 4% on $17k over four years. That’s $2700 I’m saving by leasing instead of financing. I am also saving the difference, so when that $17k is due, I will have it ready in cash to buy out the car.
If I had purchased a loaded Mazda 6 instead of the WRX (same price new), its four year wholesale value would have been $12k, so my monthly payments would have been higher, and the amount I saved in interest by leasing it would have been less (only $1900).
Would buying used have been better? Absolutely. And I tried. But the car I wanted tends to live a rough life in the hands of young drivers, and very few really clean examples show up used in Ontario. The dealership (largest Subaru dealer in Ontario) sees less than five examples good enough for them to sell every year. Thus, it made more sense to buy new, take care of it, and keep it for as long as I possibly can. (More sense still would have been to buy a used Honda Fit, but like I said, this was pre MMM).
So, now that I’ve gone on this long winded explanation of leases, should you be leasing your plug-in electric? That depends entirely on how long you are leasing it for, how much you will owe when the lease is done, and what your plan for the vehicle at the end of the lease is. If you are content to rent the car for $150/month for the rest of eternity – go for it. If you want to eventually stop having to pay $150 month in car payments, you are going to have to buy it or something else at some point. If you buy something else, the money you are paying right now is money thrown away. If you want to buy this one, you have to look closely at the total cost of the car and see just what that total amount of money could also buy you.