Energy Efficient House

[Glovepuppet1]

Hi All

Just realised I should have posted this here!

We are in the process of moving to a new property - one that is basically sound but needs some TLC to bring it back to a state of being "loved" again.

As part of our plan, we would like to incorporate energy saving measures but other than the basic everyday changes I am finding almost all kinds of micro-generation, rain/grey water harvesting, etc, to be prohibitively expensive and/or with payback times over far too long a period (eg: 20-30 years!).

Does anyone have good new stories to share? Or are positive experiences thin on the ground? It's seems such a shame that well-intentioned people with a will to "do the right thing" are not suitably encouraged to do so.

Thanks in advance for your thoughts.

insulation and draughtproofing

nothing else comes close

you need to ensure there is adequate ventilation, especially from kitchen and bathroom.

How is it heated?

Solar thermal panels are cheaper than PV (generate warm water rather than electricity.) Works well for heating but still needs a fair bit of kit to store the water and give it the occasional boost in temp. Insualtion is by far the best bet, technology will be dated quickly and will always be less efficient than the newer version a few years down the line.

Currently central heating and boiler for the hot water. It needs updating - the boiler at least, and wee suspect the central heating is approx 30 years old so may need attention too. Now would seem the time to address the situation if we are to do anything about it.

Our intention is to do the "easy wins" - insulation, low energy light bulbs, water saving measures, A+ or better rated appliances, underfloor heating in some areas, wood burner, etc. It was more the additional things overt and above that - solar thermal or PV, grey and rainwater recycling and the like, and whether that was likely to be cost effective. Or should we not bother. Your point about tech moving on is a good one.

Wood burners not very eco friendly - i think you will find these going out of fashion soon. They cause pollution.

bilbodog I've not heard that before - most places I have researched suggest that because the fuel (wood) releases only the same amount of CO2 as it absorbed during growth, it is carbon neutral so much better than fossil fuel, etc. Is this information wrong?

if you have gas, other methods for hot water are unlikely to be cost effective.

For example, my summer gas usage (hot water only) is between half a cubic metre and one cubic metre per day. A cubic metre contains a bit over 11kWh of energy I am currently paying about 2.6pence per kWh for gas. Let's suppose you spent a thousand pounds on solar hw and it halved your summer HW bill. That would be (say) 15p a day for 6 months. A payback of £27 a year. Taking 37 years to break even. Would the system last that long?

If you are forced to heat your HW with full-price electricity, it costs about four times as much per kWh so getting rid of the electricity would be a better bet. Even economy off-peak night-time rates would halve it.

Beware of money-saving schemes calculated on the assumption that you heat your home with full-price electricity. Nobody does that, if they can possibly avoid it.

PigletJohn Good points, and worth much consideration - thanks! Currently, hot water and central heating are gas so, as you say, savings through cutting out more expensive electricity would be minimal ....

Perhaps then, keeping heating and hot water by gas and opting for more efficient electrical appliances is the way to go?

there aren't many.

Heat pump driers use less energy than conventional, but cost more to buy and opinions differ about their reliability

Freezers vary a bit

Electric heaters all use the same amount of electricity to produce an equal amount of heat

Cost of LED lamps, electronics and chargers is trivial.

Your new HW cylinder will be very well insulated, but do the pipes as well.

Thanks again for your thoughts PigletJohn - much to ponder.

Does anyone else have any experiences to share?

Definitely watch out for wood burners, the co2 is indeed just released again, but they cause as many particulates as diesel engines in London nowadays, as they don't usually burn at the right temperature. I think there's a kind that will probably escape any impeding clean air regulation (because it doesn't produce the most dangerous type of smoke) and it costs more to buy and needs perfectly dry wood.
Gas is better for people directly because although it releases co2 that was locked up for a lot longer than the wood was, it doesn't produce as much localised pollution.

Oh and regaling the rain water, the simplest thing is to get a water but if you have a garden. It's not as efficient as full harvesting but it helps.
We got our extension roof designed by the structural engineer to be able to take the weight of two large water tanks, so that if it becomes viable to flush the loos from recovered water in future, we can do it from there.

MVHR

www.greenbuildingstore.co.uk/information-hub/heat-recovery-ventilation-mvhr/

I incorporated this in our 1989 new build to great effect.

Too many people go overboard with 'draft-proofing' and close up ALL ventilation. This can lead to condensation mis-interpreted as damp, poor indoor quality etc.

We have kitchen cooker hood and all bathrooms continuously ventilated and clean filtered fresh air to all bedrooms and living rooms.

Prevented middle son from suffering during hayfever season as the fresh air filter took out all pollen.

If you connect the tumble dryer into the system you don't need to feel guilty about using it in winter!

Tricky to retrofit but even if it is restricted to bathrooms and bedrooms using just the loft space it is worthwhile for the improved air quality - no condensation on bedroom windows in the morning.

Do not add a woodburner! Emits more NOx and PM10s than the worst Volkswagen.

Thanks for the info johnd2. As I understand it, the wood burners that are DEFRA exempt are acceptable for use even in areas with higher smoke/pollution controls (such as larger cities) and are efficient enough to produce very low levels of particulates.

In terms of the debate about wood as a fuel, I still think wood has good environmentally-friendly credentials because as well as producing relatively low CO2 emissions (equal to what the tree has already absorbed during its growth, so effectively carbon neutral) it is also renewable.

Yes trees are basically massive solar panels that produce fuel in solid form ;)
Sounds like you're ahead of me on wood burner knowledge.
Grumpy bloke you're right about mvhr, we did the same on our 1920s house, i don't think it improves energy efficiency much if at all, but we front onto a main road so having a constant fresh air from the back is good. It's like having a couple of Windows open all the time but without the cold draught.
We only did it because we got the units cheap on eBay, if you're paying full price unless it's new build with full air tightness it's not an eco thing to do.

Ps don't connect cooker fan or tumble dryer directly into an mvhr, as it needs to be balanced. We have a grease filtering recirculating hood separately from the extract vent.
Before we made the cooker hood the duct and filter was getting greasy dust stuck to it but now it all sticks to the mesh filter.

johnd2 and GrumpyOlderBloke - thanks again for your comments. Having had a look at MVHR it might not be the thing for us as we are not a new-build and are based in the relatively quiet countryside. Our plan is to use bi-fold doors to aid ventilation and to help "bring the outdoors indoors".

On a general note, it certainly opens a Pandora's Box when investigating green improvements to a house. I'm finding there are a number of technologies, all flawed in some way and usually involving high cost / low return, marginal benefits environmentally and inconsistent "facts".

I'm beginning to wonder if it is such a good idea after all - noble, maybe, but more trouble and expense that it's worth? Which is a real shame as for the first time in my life I thought we could do the right thing and try to make an above-average commitment to renewables, recycling, etc.

hello, a newbie here - hope this helps.
We've had MVHR for the last 8 years in our 1880 to 2005 (and still more to add) bungalow in a small rural village. We got it mainly because of damp/condensation issues (the oldest bits!) but it is really useful to not have to open windows in summer, because of the flies and wasps in abundance here. It does make a difference in the winter, as we have a much more healthy environment, but without sacrificing all of the heat we put into the house. Will it pay for itself? Questionable in financial terms, but health and environment with a small 'e' are much improved. Do you have to have an airtight house? Being an engineer, I'm not convinced on (boring) technical grounds that anything less than a noticeable draught makes that much difference compared with going into and out of the house by a door a few times!
We also have a wood burner, but it's a Morso with an external air feed-pipe, so no draughty vent grills and it's fine for the MVHR balanced system. It's DEFRA approved re emissions, but the main thing is we only use unprocessed, properly seasoned wood; painted, treated or wood that's too wet, contribute far more pollutants, both from inefficient burning and contaminants. Also I'm choosy about the species we use, as that makes a big difference, too. Sorry to go on so long.....

Having moved last year from an A rated house for EPC purposes in Belgium to a 1774 build with a very low EPC, the latter is preferable to live in. The former rental was insulated to infinity and beyond with triple glazing etc, but was stifling in summer, even with every window in the place open, it was stuffy. The current rental is cool, even with 30 degree+ temperatures...the walls are thick, the floors tiled, and my cats are far happier this summer, as am I.

In winter, yes this place is less efficient, but we have single glazing on some windows and gaps under doors which keeps the air circulating. I haven't had as many colds since moving, and floor length thermal lined curtains and draught excluders help no end.