Earlier this week, Tucson Electric Power (TEP) — the utility service provider for nearly 400,000 customers in southern Arizona — completed a new 1.6-megawatt (MW) solar installation at the University of Arizona’s Science and Technology Park in southeast Tucson. Today, the utility is using its new solar source as an opportunity to offer its customers a new way to purchase solar power.

Starting February 1, TEP will let customers buy the clean energy directly from the utility company in blocks of 150 kilowatt-hours (kWh) as part of its new Bright Tucson Community Solar Program. To get a better sense of how much energy that is, two average refrigerators can run on 150 kWh of energy for an entire month. For each block purchased, the utility will add  $3 to the customer’s utility bill. As far as we know, there is no limit on how many blocks of energy a customer can purchase, so a TEP customer can buy all of their energy directly from TEP.

When TEP first announced the forming of the new program way back in July 2010, it said that six, 15o-kWh blocks each month would be enough to power an average household for an entire year. So do the math. That’s $18 a month and $216 each year. It may cost a little more now than conventional fuel sources, but the Arizona Corporation Commission (ACC) is letting customers lock into this $18 per month fixed rate for 20 years. So the price you pay for energy won’t fluctuate for the next two decades.

The new system is the largest solar source TEP has installed locally, but that probably won’t be the case for long. Chairman, President and CEO of TEP Paul Bonavia has already said publicly that larger systems are on their way:

“This system is the first of more than a dozen local solar projects that will be built over the next few years to help us take full advantage of southern Arizona’s most abundant renewable energy resource.”

All told, TEP plans to invest $28 million this year in solar projects and has already proposed similar investments for three more years in order to meet a state mandate that requires all utilities to add more solar to their portfolios each year until they reach 15 percent by 2025.  Translation: There’s going to be a lot more blocks available in the future.