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To Lease or To Own: Simplified Solar Calculator

| Written by Matt Grimley | No Comments | Updated on Aug 4, 2015 The content that follows was originally published on the Institute for Local Self-Reliance website at
solar calculator - flickr Derek Gavey

Now simplified, the new solar lease calculator is here.

Just enter in your zip code, electric utility, and solar array size. Then set the terms of your loan or lease to see how solar ownership stacks up against third-party options.

Purchase (cash): Customer owns the PV system from day one, pays upfront with cash
Purchase (loan): Customer owns the PV sysytem starting Day 1. It is purchased with a loan, sometimes with a down-payment and paid back at a fixed interest rate
Lease, 15-year buyout: Install company or developer owns the PV System. Customer pays a fixed monthly payment that is adjusted for inflation. At 15 years, the customer elects to purchase the system and assumes full ownership.
Lease, extension: Same as “Lease, 15-year buyout” except that in Year 15 the customer elects to extend the lease with the leasing company

We assumed a $4 cost per watt, along with the 30% federal ITC. Note that utility data is based on residential rates from EIA-861 forms, so some electric utilities’ rates might be out of date. Also note that insolation rates by zip code were gleaned from U.S. National Renewable Energy Laboratory data.

Have fun! And be prepared for our complex solar lease calculator — meant for more data mushing — due out out soon.

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