[floatrock]

Lets do some simple napkin math: Lets say a solar system will cost $25k (that should get you an 8-10kW rooftop system). Pay for it with, say, a 5% APR loan.

- 10 years: $265/mo

- 15 years: $197/mo

- 20 years: $164/mo

What are your current monthly electricity costs, and what time horizon gets you a good break-even?

Also consider what electricity costs are gonna do. The loan locks in a monthly cost, but electricity rates have lately been increasing around 3% per year. Say you currently have a $150 monthly electricity bill... in 10, 15, and 20 years that will be $202, $233, and $270/mo.

There's other ways to finance it (PPA's, leases, maybe incentives if we get serious about our energy again someday, etc.) that have their own advantages/disadvantages, but even this simple approach shows there's some wins depending on your exact consumption, time horizon, time-value of money, and what you expect your electric load to do (will you get an EV? will you adopt heat pumps? will you need to start using way more AC in the summers? etc)

[FuriouslyAdrift]

I'm in a leaky, 80 year old 3 bed 2 bath in the Midwest (that doesn't have insulation in the walls... brick and plaster). Worst in the Summer is around $100/mth, worst in the Winter $40/mth (of course gas for heat is around $80 Winter, $15 Summer for water heater, stove, etc.).

[floatrock]

Ok, sounds like it doesn't pencil out for you in your region. I have a similar size in a different part of the country with my bills consistently in the mid-$100's.

YMMV. As with most things in life, there is no one-size-fits-all. Do what's right for you.