It will take 20 years to fully pay off their installation costs. The expected life of some solar panels is less than 20 years - and most panels generate less energy as they age. And the panels will require at least some ongoing maintenance costs.

So what are the REAL net costs of this project to MV taxpayers?

20yr ROI?

Wow.

Solar panels, like anything else left out in the sun including T shirts, will deteriorate from exposure to ultraviolet light. This glide slope of performance decline is about one half percent to one percent per year. Given that the next refrigerator you buy will be more energy efficient, and the next set of lightbulbs you buy will be more energy efficient, chances are that the PV system you buy, will be the last solar system your house ever needs.

Another rule of thumb is that people that procrastinate going solar will never catch up financially, to the early adopters of the technology. Yeah, panel efficiency is slowly improving at about one quarter per cent per year but your utility company may be raising electric rates at 4 percent per year.

Arrange a consultation. Or get 3 home visits to compare the dollars to watts ratios. Federal tax credits expire at the end of 2016.

Look me up on FaceBook or see my solar page at dub dub dat canonbal dat orq

20 year ROI. Assuming technology and costs remain static over the 20 years, this may be true.
What are the odds that technology and costs will remain static?

Wait for costs to come down, do not listen to the solar salesman above.
The early adopters paid the highest costs, those who waited 10 years have seen costs come way down.
The first flat panel TV's were thousands, now they are a few hundred.
The time will come for faster cost effective residential solar, but that time is not now. Not if you're interested in a quick ROI.
Patience will reward in this matter.

@Cuesta Resident -- Where are you getting 20 years??? In California, average payback time on solar investments is ~9 years.