Best investment we've made so far

Summary of Results:

•The total cost in oil for the preceding 12 months was $1,707.79. The total increase in our electrical bills after the installation of the Geothermal system was $915.64. This gives a net savings on utility payments of $792.15 for the year (46%). Update: I paid $0.72/L at the time for heating oil. Current prices are ~$1.06/L - savings are now in the area of 60% per year.
•While the installed cost for the system was $23,076.48, we received a GST rebate of $692.29 and a grant under the Energuide for Houses program of $957.00 for a total installed cost of $21,427.19. Present buyers of geothermal systems in Ontario are entitled to a grant of $7,000 (combined federal & provincial)
•If we were to build a new house we would definitely equip it with a Geothermal system instead of a conventional combustion system (oil, gas, etc.). It is important to note that builders of new homes should not be trying to justify the purchase by saving $25,000 in utility bill savings, the cost of these systems. Rather the difference between this system and a conventional system (in our case $21,427.19 minus $10,550 = $10,877.19) is the appropriate target. Energy savings alone, at today’s rates, would see this paid back in ~14 years, but this ignores lifetime and maintenance costs which offer further savings with the Geothermal system. Furthermore, for those building or renovating a house with intention to sell, the question to ask is whether or not the home value will be improved by more than the extra investment. The bank considers our home worth much more, but market conditions are the ultimate driver for this analysis.
•The 10kW electric heater was only observed once in the first winter. It happened when we tried to increase the temperature indoors while it was -28C outside. It only operated for seconds at a time and the home was up to desired temperature minutes later. The heat pump kept us comfortable throughout the winter.
•The indoor temperature selected on the Geothermal system was 21C and was not turned down at night to avoid using the 10kW heater in the mornings (i.e. this system is more energy efficient if it is not turned down at night, unlike combustion furnaces which save money when used with programmable thermostats). The oil consumption from the previous year benefited from a programmable thermostat with lower temperatures at night (16C) and while away during the day (15C).


Conclusion:

The Geothermal system was an excellent investment. The increased value to our home is not something we focused on because we intend to keep this house for many years, though it is comforting to know we could make this investment back. The utility savings are in-line with the model predictions from Atel Air and amounted to a 46% improvement this past year. The extra we put towards our mortgage each month is offset by these utility savings.
A Geothermal system is a worthwhile consideration for anybody upgrading their old furnace, building a new home, or renovating a home for resale purposes. All factors considered, it was the most economical choice we could have made.