One of the biggest goals of building a Passive House is to reduce energy consumption as much as possible; heating and electricity specifically. A piece of software, Passive House Planning Package (PHPP), is used to calculate how many watts per meter squared will be needed to heat the home to keep it at a constant 20 degrees Celcius. The current information regarding our foundation, walls, roof, windows and doors, HRV, ACH of 0.6 etc. have been entered into the software. Get this, even the number of people living in the house are included in the calculation. Each person gives off about the equivalent of a 100W lightbulb. In a highly insulated, air tight home this can make a big difference! Lucky us, an extra 600W of energy 🙂
So, with all this taken into consideration our estimated additional required energy is 187 watts. 187 watts!! That’s not much! As a comparison the numbers are calculated as well for a house build to code; that came in at a whopping 8628 watts! So what does this really equate to? Well, if we were to run a 187W heater for 24 hours a day, 7 days a week, for 150 days a year that would work out to be $81.46!!! On the contrary, if I did the same calculation for a code built house my bill would come in at $3758.35… wow!
Here’s another way to look at it. We are currently renting an old house while we plan and then build our new home. The amount that we paid for our first oil bill in this home would pay to heat our new home for 11 years!! I’ll just let you soak that in for a minute…..
I’m amazed by these numbers! Mind you, these numbers are not exact values on what the heating cost is going to be in our new home. What these number do demonstrate though is the amazing savings that can be had by following Passive House principles. The best part of it all (besides saving money) is that we are conserving energy and still living comfortably. Saving money and helping to save the planet, sounds like a match made in heaven to me 🙂
**Note: We will have to pay for more than just these added electricity I mentioned in this post, but not much more. There is going to be a small electric coil about the size of a toaster incorporated into the heat recovery system that is not being accounted for as well as the cost of running the HRV. I used these numbers as they are the ones that I had from the energy modelling.