Any new build is going to be much better insulated, and will hopefully have fewer problems with pipes bursting. Using an electric vehicle as a battery, you could easily heat such a home for days using a heat pump. If the battery gets low you can drive it somewhere with power and charge it up, the same as you would go somewhere to buy gasoline if you ran low after several days.
A properly insulated home is much cheaper to heat and cool, regardless of the fuel.
Lets look at the math here.
A 1200SF home in Upstate NY will need 60,000-66,000BTU to heat it (depending on the region, if the insulation is good AND installed properly) per the calculator at: https://learnmetrics.com/heati...
We will use 60k BTU as we are assuming that it was well insulated and they did a good job (ie: the builder didn't cut any corners on insulation, they used good windows, etc).
The generator calculator at: https://www.generatorjoe.net/h... says that a 60k BTU AC/Heatpump will need 5kW to run, or 25 amps at 240VAC single phase.
Figuring for a worse case outage in the Jan/Feb week long cold snap (single digits and wind), we will assume that the heat pump has to run 60% of the time to keep the house at a comfortable temperature (probably a little low on runtime, its not uncommon to have a furnace run almost nonstop for those cold snaps).
That would be 5kW*(24Hours*60%)=72kWH, PLUS you need to figure in enough charge to get to a charging station that has power and the amount of power used by the car to keep the battery pack warm.
So, you could probably heat a 1200SF house in Upstate NY off of an electric car if you can find someplace that has power to charge it at least once a day.
However, many houses in Upstate NY are larger than 1200SF, using Monroe County (where Rochester is), per https://www.redfin.com/county/... the median home sale price was $200k and the median price was $137/SF, that works out to 1459SF, the state average is over 1700SF per: https://www.bobvila.com/slides...
Using the same sources as the 1200SF house, a 1500SF house would need a 75,000BTU heat pump (6.5kW, 93.6kWH/day) and a 1700SF house would need a 85,000BTU heat pump (7.5KW, 108kHW/day).
That also does not include the efficiency loss you get from trying to run an air source heat pump in temperatures that low.
So, could you not heat a "average" Upstate NY house in the middle of the winter with electric heat from a Tesla car battery (IIRC they have the biggest battery of any of the "readily available" EVs at 75-104kWH) unless you could charge it more than once a day.
If that much power is out, there is a good chance that it will be at least a day before the roads are passable from downed power lines and trees.
Aaron Z