Home energy saving tips /ideas...

[rogerzilla]

It's sufficiently warm weather that the stove can't really be lit, so the CH is on.  It won't cost much to run when it's 12-13°C outside.

[Kim]

Tragic that we need articles like this, and equally tragic that it's so vague (but I suppose that's what you get when you get finance people to cover engineering subjects): https://www.bbc.co.uk/news/av/business-63910430

Also misses the point that LED fairy lights are a much cheaper and safer alternative to candles in the event of those power cuts we've been promised.

[Cudzoziemiec]

Bike lights probably give you more lumens for your lsd though (compared to fairy lights).

[chopstick]

Bike lights probably give you more lumens for your lsd though (compared to fairy lights).

Mine certainly do on account of being "dynamo" - but I don't fancy bringing the rollers into the living room - tbh I don't fancy using the rollers at all.  I could top up the powerbanks whilst out in the day though.  I think I'd rather sit in a room with fairy lights than a bike lamp (unless I was reading).

[Mrs Pingu]

This article is quite interesting. Needs legislation though....
https://www.theguardian.com/environment/2023/jan/12/energy-house-20-tests-tech-that-aims-to-make-homes-greener-and-cheaper-to-run

[rogerzilla]

Insulation is an odd one.  It works fine when there is a constant temperature difference between indoors and out.  However, many people leave the heating off during the working day and only switch it on when, or just before, they return home.  You'd be silly not to.

Anyway, when trying to raise a house from stone cold, the insulation doesn't speed this up appreciably.  Everything on the indoor side of the insulation has to be warmed up, not just the air.  To do that quickly and with minimal losses, you need a powerful heat source.  My mid-90s new build was only acceptably warm at weekends in winter, because the CH simply couldn't get it to temperature between 4pm and bedtime.  That had modern, not much different to current, insulation thicknesses.

[DuncanM]

Presumably, the insulation reduces the temperature drop between turning the heating off and turning it back on again though?

As far as "smart" TRV things, we have TADO with "smart" valves on all our radiators, which means that the heating is on in the bedroom/office, but nowhere else right now. Every so often it tells us how much it has saved, but I don't believe it for a second. We don't pay for the subscription, so can't set up geolocation based heating, but that seemed like too much of a faff even when it was free.

[grams]

Everything on the indoor side of the insulation has to be warmed up, not just the air.

In a poorly insulated house you have to not only heat up the air in the house but the outside of the house too, which has the annoying habit of drifting away.

I think you may have learnt the wrong lesson from whatever houses you’re comparing. It sounds like the heating wasn’t working properly or the insulation wasn’t doing its job.

[chrisbainbridge]

Insulation is an odd one.  It works fine when there is a constant temperature difference between indoors and out.  However, many people leave the heating off during the working day and only switch it on when, or just before, they return home.  You'd be silly not to.

Anyway, when trying to raise a house from stone cold, the insulation doesn't speed this up appreciably.  Everything on the indoor side of the insulation has to be warmed up, not just the air.  To do that quickly and with minimal losses, you need a powerful heat source.  My mid-90s new build was only acceptably warm at weekends in winter, because the CH simply couldn't get it to temperature between 4pm and bedtime.  That had modern, not much different to current, insulation thicknesses.

We had a similar discussion with our central heating installer in our newbuild.  The response was that CH should be left on constantly at a low level and the bigger the house the more important.  They deliberately under specced the boiler and piping in order to get the contract and I did not spot it.

[rogerzilla]

Most houses need bigger radiators.  The problem is that there's nowhere to put them in modern shoeboxes.

[rogerzilla]

I took the moneysavingboilerchallenge.com and failed.

They don't recommend it if you have a hot water cylinder, which is correct as you'd never get properly hot water.

They also say the average boiler creates the same CO2 in a year as SEVEN transatlantic flights.  Why are we worrying about flying?!!

[Pickled Onion]

I took the moneysavingboilerchallenge.com and failed.

They don't recommend it if you have a hot water cylinder, which is correct as you'd never get properly hot water.

They also say the average boiler creates the same CO2 in a year as SEVEN transatlantic flights.  Why are we worrying about flying?!!

I don't know, it beats me. The total emissions from aviation account for 2% of global CO₂. That's all aviation, freight, crop spraying, everything, not just pointless business meetings in Singapore or multiple package holidays to Magaloof. If we grounded every plane permanently tomorrow it would make a gnat's crotchet of fuck all difference to climate change.

[mrcharly-YHT]

I took the moneysavingboilerchallenge.com and failed.

They don't recommend it if you have a hot water cylinder, which is correct as you'd never get properly hot water.

They also say the average boiler creates the same CO2 in a year as SEVEN transatlantic flights.  Why are we worrying about flying?!!

I don't know, it beats me. The total emissions from aviation account for 2% of global CO₂. That's all aviation, freight, crop spraying, everything, not just pointless business meetings in Singapore or multiple package holidays to Magaloof. If we grounded every plane permanently tomorrow it would make a gnat's crotchet of fuck all difference to climate change.

Not correct.

It isn't just the CO2, it is the particulates and  water vapour dumped right where they have the most impact.

[MikeFromLFE]

Most houses need bigger radiators.  The problem is that there's nowhere to put them in modern shoeboxes.

Or anywhere to put the bikes.

[Mrs Pingu]

Well.
Just under 4 months after I submitted the claim forms, Home Energy Scotland have just called and are going to put us in the payment run for next week so we can get our money for the CWI and underfloor insulation we had installed in July.
Finally!
<dances frenetically>

[HTFB]

Insulation is an odd one.  It works fine when there is a constant temperature difference between indoors and out.  However, many people leave the heating off during the working day and only switch it on when, or just before, they return home.  You'd be silly not to.

Anyway, when trying to raise a house from stone cold, the insulation doesn't speed this up appreciably.  Everything on the indoor side of the insulation has to be warmed up, not just the air.  To do that quickly and with minimal losses, you need a powerful heat source.  My mid-90s new build was only acceptably warm at weekends in winter, because the CH simply couldn't get it to temperature between 4pm and bedtime.  That had modern, not much different to current, insulation thicknesses.

Insulation of course slows down the losses from everything inside it, including the walls. So a well-insulated house shouldn't get stone cold before you come back and heat it up again.

A new-build house will take the savings from the lower heat loss and cash them out in the form of a smaller boiler, smaller radiators, and lower flow temperature. As you say, the properly-sized system can keep the house warm but what it can't do is crash-heat it in a hurry when you get home. You are supposed to leave the heating on while you are out, with a high-ish "set-back" temperature. The insulation means it doesn't actually lose much heat in the meantime, and running a small system at its design capacity is more efficient than blasting a large one briefly, so you save fuel overall.

"You'd be silly not to" is the sort of BRITISH reasoning that means we live shivering in expensive but still cold and damp homes and die young of unspeakable respiratory disease. (We did a study a few years ago giving people hybrid heat pump / gas boiler systems. Even though running the heat pump overnight on Economy 7 electricity is vastly cheaper  the residents preferred to let the house cool down and then rely on lots of gas. They liked cold bedrooms and couldn't get around the idea of heating the downstairs when they weren't in it yet. This counts as a policy failure.)

[MikeFromLFE]

I've done a few amateur back of an envelope experiments with leaving the heating off or on when we've been out all day.
The costs seem to work out to be almost identical - although it's nice to come home to a warm place rather than waiting for it to warm up.
Impossible for me to compensate for variables such as weather though.

[Mrs Pingu]

I would imagine that having the boiler running more often but at a lower flow temp with more condensing going on is probably better for the boiler than more periods of going full gas to heat up from cold to hot.

[Cudzoziemiec]

Depends on having a thermostat though. If you don't have a thermostat to cut the boiler off when the room reaches the desired 'uninhabited' temperature, you're going to come back to a very hot house and a huge bill.

[Kim]

Who has central heating but no thermostat or TRVs?

People with cold houses and huge bills, or who never use the central heating, presumably.  And I suppose a few victims of landlord shoddiness.

[Cudzoziemiec]

Our old boiler had a thermostat, but it was in a pretty useless place, the hall. Easy to wire into the boiler but not much good for actual thermal regulation. When that boiler broke down, the new one the landlord put in had no thermostat. But it does seem more efficient, and he did put it in promptly without getting multiple quotes!(!) We put it on two or three times a day as necessary, definitely not at night or if we're away.

[Kim]

Actually, I've just remembered installing a thermostat at Mrs Barakta's-Mum's former residence, which didn't have one.  It did have TRVs though, so it's not like it was unregulated.

[Cudzoziemiec]

Actually, a quick shufti at Screwfix suggests we do have TRVs. Probably these ones: https://www.screwfix.com/p/flomasta-white-chrome-angled-thermostatic-radiator-valve-lockshield-15mm-x-1-2/386xt
I can't see an actual brand name on them. I'd both a) interpreted TRVs as something 'smarter' (like with actual temperatures rather than scale-less markings) and b) not noticed them doing anything. As you were, then.

[Feanor]

Yes, those are TRVs.

They typically are uncalibrated and don't work in actual temperatures.
That's OK, because where they are situated means that the temperature they see is not the room temperature.
You just need to adjust as-required.

Once they reach their set-point, they just throttle the flow to the radiator.
Once all the radiators are throttling, the flow will be reduced in the loop, with the only flow remaining in the bypass radiator ( usually a towel rail ) or a pressure relief valve.
At this point, the return temperature to the boiler will be almost as hot as the flow temperature, and the boiler will shut down on it's own internal thermostat, which will usually have a dial on the boiler itself.

[Cudzoziemiec]

Okay, will have to experiment with leaving the heating on and seeing what happens.