Energy Crisis - Can HA Help?

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Hi everyone,
The UK (and to a hopefully lesser degree, Europe) is currently in an energy crisis.

Annual bills have jumped from averages of £1200 a year up to £3000 for the same usage patterns (latest figures available based on what the next price cap calculation will be in October).

I can’t afford this long term (no pay rise since 2019, recent divorce with a daughter to support, not long moved into a new house so very little savings to fall back on) and assume many others are in a similar position.

So I was wondering if people could share suggestions on energy saving automations/ideas.

Obvious ones like auto lights stand out, but when it’s controlling a LED bulb it may not be that useful (but every little helps!).

Zoned heating using either zigbee thermostatic radiator valves, or, I plan to use thermostatic actuators (mains powered, 2w while in use) to save on batteries (and cheaper than TRVs) could apparently save around 20% on your annual bills.

I had considered a temperature sensor in the fridge/freezer and turning off the fridge overnight - however I am concerned that the compressor wouldn’t like this over time and could cause premature failure.

Turning off associated peripherals when computers/TVs are turned off.

I’m trying to work out a way to gracefully shut down my unraid box overnight (I mainly use it for media serving, if I’m asleep I don’t need that).

I’d love solar, but it would only be a relatively small east/west split so wouldn’t help too much, and in my area there’s a waiting list until October to get installs so would be into winter by then and onto the next price cap rise - not to mention it would wipe out my savings so Is a bit gamble.

These may all seem obvious but I didn’t do any of these previously, so hopefully should see a noticeable cut in usage.

if anyone else has suggestions, post away. I hope to take away some other ideas as well as hope my ones help others out.

(I put this here and not share your projects as it’s more of a chat, hope that’s OK)

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When it’s time to crunch, hard choices, many of your observation will help, just need to start doing them.

Here are a couple more.

  1. Set heating / cooling temperature way back
  2. DO NOT cycle the Refrigerator’s power supply. Simply raise the temperature on the thermostat to save energy.
  3. Hang your clothes to dry, instead of use a clothes dryer.
  4. Lower your water heater temperature.
  5. If you have time metered service, do as much as you can during the cheaper hours (clothes, Dishes, Cooking, etc).
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Thanks for clearing up the fridge thing!

Unfortunately (or fortunately!) my home is quite well insulated, as a result if I put clothes out to dry naturally I get a stale musty smell and bad condensation on windows.

My plan was a power monitoring plug (just for monitoring) and a desiccant dehumidifier. Should be cheaper to run than a tumble drier and I tend to have to wash a lot (I have a 4 year old).

I’m also trying to work out how to tell if I have visitors, if I have visitors make the house ‘behave normally’ and if I’m there on my own light and heat the bare minimum. Other than person detection in my porch counting people in and out I’m not sure how else to do it.

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Weather permitting hang your clothes outside if you can.

If the visitors are just a few hours, then I would just setup a ‘bypass’ in the energy automation. If the visitors are “staying” and are regular (in-laws come to mind) connected them to your wifi and then add their devices to the bypass.

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Been thinking about this also.
I’ll be looking at solar PV next week as possible longer term investment, given that I have an EV coming later this month. Living quite far north, I’ll not produce for at least 3 months of the year.
I have zoned heating already and I monitor my energy consumption.
Biggest consumption comes from cooking and electric shower. Cooking appliances are old, so need to check if newer ones would be worth it.
The clothes dryer is surprisingly efficient.
Unfortunately it doesn’t seem like there’s any quick fix. Solar PV, good insulation and air source heat pump seen the only to reduce energy bills significantly, but they all represent large investments and will take 5-10 years to come good…

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With maybe Mitsubishi Hyper Heat type unit being the exception, I’m not sure a traditional air to air heat pump would be a good choice in a very cold climate.

I’ve noticed when I got to a certain point in energy conservation, it became exceedingly expensive to achieve a greater reduction in consumption. Couple that with the useful life expectancy of equipment it becomes even more difficult to recover those costs.

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Fair warning. I got a couple quotes for solar recently. They said they were fully booked for installs until late October (UK) then bad weather would stop play until this time next year.

The previous owner of the house fitted a 10kw shower, it’s lovely and hot and the pressure is amazing… But it costs a bomb to use… Seems silly to pull it out and replace when it’s working fine and relatively new so I’m going to make a shower timer with home assistant to flick the lights off or play annoying sounds on a Google home to train me to have faster showers.

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From what I have been reading, the main issue air source heat point is that when the dew point is around 4°C to 8°C, I’ve forms over the heat exchanger, causing the heat pump to cycle Which affect efficiency by about 20%.
Unfortunately, these conditions are common here.

Science

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So, I have been looking at solar PV, to potentially benefit from running the base load for the house , heating hot water in the summer and charging the car with the excess power produced. There are appliances that can do that (Zappi and eddi devices come to mind), but Im thinking that HA could do an even better job. This would require a few things. For example, the Tesla integration lets you set the charging load, which would be enough to ensure that solar pv excess is used to charge the car battery. unfortunately not all EVs provide this ability (yet). As for immersion heater, surely it shouldn’t be too hard to devise something that can regulate the load (0 to 12A), controlled via MQTT.
The other two practical things that I am doing are: reducing the house base load and controlling the heating to take into account the weather forecast.
I’ve managed to reduce my base load quite dramatically switching off thing like amplifiers, TVs, lights automatically when not in use/no presence. At night, my base load is bellow 70W.
As for heating, I know that from March to Oct, if it’s a sunny day, I don’t need to run the heating at all. I have an integrated drayton wiser system with valves in every room, and if it is the case that it will be a sunny day, I put the the heating on away mode. The house is cooler in the morning, but warms up during the day. Also, door/window sensor are used to ensure that the heating isn’t called by the smart valves if a window is open.
Small savings, but they do add up I guess.

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Why limit it to overnight? I’m not familiar with unraid but (assuming you can ssh to it), you could put it to sleep pretty much on-demand. This can depend on your media playback setup though - in my case pretty much all media playback starts on a Linux device somewhere so autofs can trigger a WOL packet when needed.

I shifted a bunch of stuff off of a home NAS to a small Pi cluster for the reason you mention - having the server sleep unless it’s needed. Took a bit of tinkering to get right but the NAS box is typically now averaging between 10% and 20% of the time it was. Ironically the most power hungry thing in that Pi cluster is an oldish network switch.

Judging by historical data in Grafana, it’s saving about 1 kWh/day - or ~£100/year based on current electricity prices. Of course YMMV depending on what you’re running Unraid on…

The bigger question I have is how many of these things can be done without extra investment. A single Pi kicking around to run HA or similar on is one thing but if you start needing to buy sensors, gateways etc. it gets counter productive.