Converting our home to zero carbon emissions has been a minefield.

Here’s what went wrong:

After trying, unsuccessfully to build a home (thanks @cityoftoronto for a two year permitting process) we bought a new home built by a respectable custom home builder.

Fortunately it was well air sealed at 1.4 air changes per hour and well insulated.

Unfortunately it was built with two gas furnaces, gas hot water tank, and gas range. The Canadian Special.

I - in my infinite wisdom - decided that we should convert to zero emissions.

Let the games begin.

1. Our electrical panel was too small.

We had a 40 slot panel with 200 amp service. Heat and hot water alone now take 15.

Solution: Install a bigger panel ($2K ish)

2. Too much current

Two heat pumps would draw a max of 90 amps ((40 + 5) *2)

Each needs an electric backup - in case weather drops to -30C - that draws 60 amps each.

That’s 210 just for heat.

Solution: cut the breaker to the aux heat and hope for -25C or above.

3. Electrical panel is too dumb

Besides electric heat and hot water, we have:
- a hot tub (30-50 amps)
- EV charger (20-50amps)
- washers and dryers (10-15 amps each)
- range (up to 40 amps)
- fridge and freezer (15 amps on startup)
- sump pumps
- etc

Ideally, our electrical panel would be smart enough to “interrupt” less important, high draw items like the hot tub or EV charger when total demand exceeds the 200amp supply. Nope.

Solution: if it gets really cold, turn off the hot tub and/or stop EV charging.

4. No induction ranges big enough

We have a 48” gas range. There is only one company, *in the world*, that makes a 48” induction range we can replace it with. It’s $14,000 and isn’t widely available.

Solution: car priced range

5. Wrong Hot Water Tank

My HVAC company recommended the wrong hot water tank (15 amp instead of 30). It’s slower to recover (16 gph vs 27). It’s fine, but you should go with the 30 amp.

We’re fortunate enough - both financially and in my wife’s patience - to decarbonize our home. But for most people, decarbonizing won’t happen until 1000 little frictions disappear.

If we’re serious about decarbonizing, we should be mandating these in new homes:

- 200 amp service (or more)
- smart electrical panels
- EV, heat pump, and hot water tank rough ins
- Stricter air change requirements

We should stop subsidizing natural gas upgrades and immediately start subsidizing:
- electrical service upgrades
- electrical panel upgrades
- heat pumps
- electric and hybrid hot water tanks
- EV chargers

The technology to go zero carbon is here, it’s just not evenly distributed.

For those interested, we converted to:
- Two Mitsubishi Zuba heat pumps
- Rheem Proterra Hybrid Heat Pump Hot Water Tank
- AGA induction range