Yesterday we decided to take the plunge and told gave our electrical contractor/installer a deposit. We felt pressure to make a decision before the March 31st deadline, at which point the State of Minnesota’s incentive drops from $2.25/watt to $2.00 per watt (which would be an $840 decrease in the State rebate). The solar system does not need to be installed by then, it just needs to be submitted to the State and installed within the next nine months.
I’ve got a few things I am concerned about (is this already buyer’s remorse)? First: the system we are getting is not yet UL listed. That means not only is it not eligible for any of the rebates or tax incentives, it also might not be safe! But the good folks at TenK Solar assure me that they will be UL listed very soon.
Second: the installer we chose is not yet NABCEP Certified, which means one of the incentives would drop by $0.25. He assured me, however, that he will be NABCEP Certified by the time of installation, and that’s what matters. He took the test last week, and he will also pick up that $840 cost if I do not get the rebate due to him.
Third: I originally did not want a system with a battery back-up. We live in the city and are connected to the grid, and there are rarely any power outages. We also have a back-up generator in the event of power outages, mostly because we live on a very wet piece of land and we MUST have our sump pump working all the time, or our basement will get wet, and there will be mold, and I am terribly allergic to mold, and all that work and time and money putting into a healthy a home will go down the tube. Getting back to the battery system….TenK’s battery-less system uses an inverter that makes a constant humming noise. That would not be good, whether it is placed inside or outside. Solar is supposed to be quiet! So, we are going with the quiet inverter, but it also requires batteries. So now we will have two back-up power options. Overkill? If there is a disruption in the natural gas line, we will be thankful!
Now the good news. I had always thought that each kilowatt produces about 1,200 kilowatt hours per year, on average (see previous post under solar). However, because the TenK Solar system has reflectors that reflect more sunlight towards the photovoltaics, our 3.36 KW system should produce about 4,580 kilowatt hours per year. We have lived in our house for one year, and according to my estimates, that should take care of about 38% of our electrical needs. (That does not include the electricity required to run our ground-source heat pump — which is on a separate meter.) It also equates to savings of about $450 about 7,400 pounds of CO2 emissions per year.
If you do a simple payback analysis, net of rebates and tax credits, the cost of the solar system pays for itself in about twenty years (assuming electricity costs remain relatively flat). But what if we put a value on our reduction in carbon emissions? At TerraPass, an organization that sells carbon offsets and uses that money to fund clean energy projects, it costs $13.12 per ton to offset carbon emissions. If we offset about 7,400 pounds of CO2 emissions per year with our new solar system, that’s worth about $50 per year! Wow. Global climate change, here we come.