Detailed Geothermal Analysis in Cincinnati, Ohio
The following numbers are all in kWh, and for my single-family house that is about 2,000 square feet, plus basement. All heating is electric. My electric bills usually come in around the 17th to 20th of the month. In the data below, an October value is actually the usage from the second half of September to the first half of October.
The data is current as of 5/24/2017. I’ll try to update this monthly.
kWh Usage Details, Monthly
Below is a breakdown of my monthly electric usage since late 2007. The blue cells is my usage when using an inefficient air-source heat pump (probably 10 or 11 SEER). The green cells is my usage since installing a geothermal heat pump.
kWh Usage, Monthly Average
Here is a summary of the above table. The blue cells is the average, per month, of the blue cells from the table above, and the green cells are the average, per month, of the green cells above.
In the summer months I’m obviously not really saving any (significant) money, even when compared to the 20-year old, inefficient air source heat pump. I never did use much electric (for cooling) in the summer months though.
Based on the “Monthly Average” data above, I’m saving about 6,094 kWh per year. At my current electric rate of about $0.10 per kWh (it varies slightly month-to-month), the yearly savings from upgrading to geothermal is $609.40. This translates to a 22.4% savings per year over my previous electric bills.
When I purchased my geothermal unit, my existing heat pump was broken. I received various estimates for replacement – the average of which was around $8,500. The final cost of the geothermal heat pump from Arronco came out to be around $13,500 after tax credits and rebates. If I assume that a new air source heat pump would have similar performance to my old air source heat pump (which probably is not a good assumption), the return on investment would be roughly 8 years. However, since a new air source heat pump should be more efficient than my old air source heat pump, I’m guessing that a more realistic ROI would be closer to 10 years.