Homes that are energy efficient require a smaller solar system than those that are not. Therefor, you should make as many efficiency upgrades to your home before you get a solar electric system… right!?
Well, not necessarily. 10-15 years ago, the cost of solar was extremely high. That’s no longer the case.
When thinking about potential efficiency upgrades, it’s important to consider how much they’ll impact your future electric usage. First, compare your electric costs during the summer months to other months in order to get a rough idea how much you’re spending on air conditioning. Is it $200 a month for three months each summertime? $300 for four months?
Well, new efficient windows can save you a portion of that extra cost. Same with a new efficient air conditioner. Remember that if you don’t have an air conditioner, then efficiency won’t save you anything at all!
Next, consider how much these efficiency upgrades cost. After looking at the cost vs. the savings, many homeowners decide to forego the efficiency upgrades. A new air conditioner, for example, may cost $10,000 or more to install, and might save the homeowner just a few hundred dollars each year. The same utility savings could be achieved with just $1,000 – $2,000 of solar instead.
There are cases though in which efficiency can be a good investment. LED light bulbs are perhaps the efficiency investment that pays for itself the fastest, and the quality of light now is good. Caulking around windows and doors is very inexpensive, and can save on energy costs to heat or cool your home. Insulation in your attic can be an inexpensive way to save on energy costs too, especially on the cost of heating (this will save you gas more than electricity). And replacing an old pool pump with a new efficient variable speed pool pump will generally pay for itself in energy savings fairly quickly.
And there are other legitimate reasons to invest in efficiency, having more to do with comfort than with economics. Dual pane windows may reduce hot spots and cold spots in your home, and can block some outdoor noise. New efficient air conditioners are quieter and cause less air turbulence, and can improve your indoor air quality.
But if your motivation is primarily economic, postponing solar in favor of major efficiency improvements just does not make financial sense. A dollar spent on solar will save you MUCH more than a dollar spent on a new air conditioner or new windows. And the 30% federal solar tax credit will start stepping down after 2019, and will disappear altogether for systems installed after 2021. So if you’re going to get solar, it makes sense to do it now. Then think about major efficiency improvements at your leisure.