u/Draknurd

The main selling point for heat pump hot water is the lower power draw that these appliances have, while conventional resistive hot water systems use a lot more power (~3-4x?). But resistive heaters are cheaper upfront.

Let’s say I’m speccing out a 250L system. The upfront cost of a conventional twin element system is about $1,500–$1,900 compared to about $5,500–$6300 for a heat pump system (plus labour).

With three hours’ free power in the afternoon, I could get the twin element conventional hot water system to heat to 70°C (I have a tempering valve) using the bottom element in the three hour period. Even from a cold start, that should be enough time to heat the whole tank.

Outside that, the top element would kick in the top half of the tank if it detects water getting below 50°C.

There’d be some usage cost for the top element (to 50°C only) if lots of water is used, or as the tank cools during the day. But it should take some time for the water in the tank to drop to 50°C in the first place. Therefore most of the main heating would be free.

Conventional water heaters are also so mechanically simple with no moving parts. Chances of a breakage are much lower.

Based on this usage, does it make any sense to install a heat pump system?

I randomly remembered an old midi player that ran on my family PC in the windows 95/98 era. I can picture it but I can’t for the life of me remember the name. It *may* have had the word lava in it but I don’t think it’s the Creative program.

- In my case it came on one of those magazine CD-ROM bundles
- Its interface was black and blue with 3D blue buttons
- Each midi voice had a little gauge over it that would fill will animated flames when a note was played
- There was a set of buttons at the bottom of the window you could use to play notes that were tuned for the playing track
- I think a metronome played by default
- One bundled track was something like “autoload” and another was “dance groove/dancegrv”