CleanTechnica is the #1 cleantech-focused
 in the world.

Buildings home energy calculator

Published on December 19th, 2013 | by Zachary Shahan


New California Green Home Calculator Compares You To Neighbors, Shows Your Financial Savings

Originally published on Cost of Solar.

Build It Green, a California-based nonprofit, has created a new home energy calculator that shows you how much greener your home is compared to your average neighbor’s home. It also shows you how much money you save compared to your neighbor.

I decided to play around with the cool new calculator a bit. I’ve seen many of these, but this certainly one of the most sophisticated I’ve seen, maybe the most sophisticated. I don’t have a home in California, so I was just throwing in some fake info. After changing a few things in the “Interior” section, my home was 6% greener than my average neighbor’s (using a San Francisco area code). Interestingly, though, and showing just how super green solar panels are, when I moved on to the exterior and said that I had solar panels, my “Green Home Score” jumped to 55%! Furthermore, my savings jumped from $75,140 over 30 years to $107,246, showing that going solar isn’t just about being green, but it’s also about saving “green.” Here’s a snapshot of my (fake) home at that stage:

home energy calculator

How much will solar save you?
Find out in about 60 seconds!

Even if I say I don’t have central air conditioning, don’t have a dishwasher, don’t have a refrigerator, don’t have a washing machine, use 100% green (CFL/LED) lighting, and have insulation everywhere possible, I only get up to 29% greener than average (and $87,530 savings) without the solar panels. In the solar situation above, I have all of those appliances and don’t have insulation in my walls.

In both situations, I put that I had electric heating and water heating. With heating and water heating coming from natural gas instead, and all other variables except the solar panels at default, my home is 26% greener and I save $18,891 over 30 years. Default, of course, has me at 0% and $0.

Anyway, as you can see, this green home or energy calculator is a lot of fun to play with. The options to change variables are tremendous. Go ahead and give it a shot, especially if you live in California.

But the big conclusion is that solar panels are the best way to green your home (without removing just about every modern amenity in your home), and that’s especially the case if your heating comes from electricity.

Cost of Solar readers would already know much of this, though, wouldn’t you? You know that solar panel costs are a small fraction of what they were just a few years ago. You know that solar panel savings are now huge due to that. You know that the average Californian who goes solar is likely to save over $30,000 over 20 years. You know that the rooftop revolution has arrived. :D

Print Friendly

Tags: , , , , , , , , , ,

About the Author

is the director of CleanTechnica, the most popular cleantech-focused website in the world, and Planetsave, a world-leading green and science news site. He has been covering green news of various sorts since 2008, and he has been especially focused on solar energy, electric vehicles, and wind energy for the past four years or so. Aside from his work on CleanTechnica and Planetsave, he's the Network Manager for their parent organization – Important Media – and he's the Owner/Founder of Solar Love, EV Obsession, and Bikocity. To connect with Zach on some of your favorite social networks, go to and click on the relevant buttons.

  • Don Knapp, Build It Green

    Hi Marion, thanks for your feedback. But based on your comment, the calculator was probably correct and did not make a mistake. As I think you may have realized, the energy use figure of 6,750 kWh is a combined number for both electricity and gas (BTUs converted to kWhs), so that’s why it is larger than your typical electricity usage, but still probably a reasonable estimate. So your bill would not really be $2,250/month, thank goodness! You do make a good point about splitting the electric and gas bills — it might be less confusing and we will take this into consideration for a future update of the calculator.

  • Jamie DeVriend

    I think that even if the calculations may not be entirely accurate, it’s still fun to play with. I’m glad you posted it! Even so, I also think it’s clear that there are significant savings to be had by switching to solar. I tell locals when they’re looking at solar companies in Sacramento to just call them, call SMUD (local utility), and then do the math.

  • Marion Meads

    Whoa! There is big miscalc in their calculator.

    I entered a 4,000 sq ft home, and our neighborhood average energy use is 6,750 kWh/month!!! That would be $2,250/month to PG&E if these were all electricity. I pay less than that for my mortgage, and my electric bills without solar is about $200/month for 900 kWh/month.

    I think they should redo this portion. Better to split the electric energy bills and the gas bills.

Back to Top ↑