by Chris Wade

We recently posted information about a new photovoltaic solar energy project that has just been installed right here in Vermont. The project consists of 36 AllSun Tracker panels installed on an acre or two of land. The installed cost of each of these panels is said to be about $31,000 and on average each panel generates about 470 kwh per month. This is really pretty cool stuff and the cost of this type of installation is becoming more affordable and can be justified at least to some degree based on the energy saved and the environmental benefits.

What I don’t get is why it makes sense to put this type of financial resources into technologies that offer what have to be called pretty abominable rates of return. I know they are aided by very significant tax credits but those credits unfortunately don’t grow on trees – they come from all of us in the form of higher taxes, higher deficits, or both.

I am not saying that investing in solar technology doesn’t make sense. This type of subsidy will allow costs to produce this type of equipment falls it can play a large roll in reducing our dependence on carbon based fuels and the tax credits hopefully will give solar and wind energy the boost they need to become viable.

What I am saying is that we are enamored with the concept of wind and solar energy, and like most romantic relationships you think with your heart and not your head. Unfortunately I recall a time in our industry during the Carter administration where government subsidies help create a vibrant solar and heat pump industry, which promptly died in the early 1980’s as these subsidies where removed and it became obvious that the technology could not stand on its own.

There are many ways that we could invest the type of resources committed to the Hinesburg Solar array that would yield vastly better results, both in terms of environmental benefits, energy profiles, and financial returns. Investment in weatherization and updated residential technology can sharply reduce energy consumed and provide simple rates of financial returns far better than the 2.6% projected in our photovoltaic project.

For instance lets compare the $31,000 investment and the 470 kwh produced each month to what we would save by using heat pump technology to improve residential domestic hot water efficiency.

The University of Illinois just place first in hot water category of the Solar Decathlon by utilizing an air to water heat pump for domestic hot water production. If we utilized our $31,000 to retrofit 21 homes with electric hot water tanks with a heat pump water heater we would save about 7400 kwh per month and reduce peak generation needs by about 66 kw.

So in a solar array $31,000 buys you $67 worth of power per month and an ROI of 2.6%. Retrofitting water tanks doesn’t create a great photo-op but using heat pump technology $31,000 buys you $1060 in energy savings per month with an ROI of over 40%.

Going from basement to basement installing heat pumps isn’t sexy, and plumbers as a group are not exactly photogenic, but shouldn’t environmental and financial performance count for at least as much as a good looking pictures and a compelling story in the news?

This entry was posted on Saturday, October 31st, 2009 at 10:19 am and is filed under My Government, My Home, My Local, featured. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.