That's a neat proxy measurement to track.

Me and my cofounder run https://www.pipelien.com, sales software that tries to automate the busywork. While we’re building for 4 months now and officially still in stealth, our waitinglist are 80% battery and heatpump sellers in the Benelux. It really seems to have its moment :)

A heat pump could win as the best HVAC technology, though a better drilling for ground-sourced ones. Just a shallow drilling (up to 100m) that works in retrofit mode, such as drilling from the basement, would be a great upgrade:

- No outdoor unit that looks awful in many settings

- works well, even in the coldest winter, without a spike in electricity usage, COP 5

- very reliable with long durability

- super quiet, no ambient noise

- 20% more efficient

Currently, drilling is very disruptive in retrofits, but there is progress in compact techniques that might change the equation.

Disclaimer: angel investor in https://www.flexdrill.at/

I think it's a little more nuanced than people simply reacting to high prices. In Denmark we've seen various initatives and incentives to make people replace their fossil fueled heaters since the invasion of Ukraine in 2022. There is also regulations pushing people away from their previous heat sources because of added taxations on non green solutions. I'm sure the price hike has a big effect, every time there are price hikes more and more people replace their equipment as they give up on the idea that things will ever really return to normal.