Your Solar Savings Estimate
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Tom, this is what solar looks like for your home...
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You Dakota Electric bill is averaging $250 per month. Based on the typical rates in your area your recommended solar installation size is 19.3 kW.  
Your Solar Offset is 99%. 

Montana requires all investor-owned utilities to offer net metering. With net metering, you get a full retail rate credit for the amount of power that you don’t use and send back into the power grid. The surplus energy is applied as a credit to your next monthly bill. During peak months you can generate power to be used during non-peak months. If your solar system consistently provides more power to the grid than is needed, we believe that you should be entitled to compensation. Also, you can consider Montana Solar Rebates, State Tax Credits, and Property Tax Exemptions, and the Federal Solar Investment Tax Credit. 

Up-front cost of a typical installation in Minnesota (based on 19.25 kW system)                        $60,546
Federal Investment Tax Credit (ITC)                         -$15,742
Based on your  $250 average energy use now and a 2.2% annual increase in energy prices over the next 20 years you'll expect to pay $74,535 in energy costs. 

Going solar (with the ITC tax credit of $15,742) would run you a total investment of $44,804. 
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