Do Green technologies pass the CLUB test?

[The Natural Philosopher]

Complete Load of Utter Bollocks.

Apart from LED lightbulbs, can anyone think of any green technology that isn't worse than what it purports to replace??

[John Brown]

The Natural Philosopher [e-mail] wrote

Passive solar design and excellent insulation and good sealing with a new house.

Using a heated throw, an electric blanket you use on an armchair or sofa, instead of heating the entire house or room when sitting around most of the time.

Wearing well insulating clothes in the winter.

[Martin Brown]

Be careful. They guard their IP rather vigorously.

This one is my favourite of the green energy Dilbert cartoons.

The evil Dogbert power company.

Some of the passive cooling metamaterials might be interesting in the future. There is a new whiter than white paint does it too. How long it will stay white for in actual use is a trick question though.

Could well be a laboratory curiosity only.

Electric cars inside cities do have some advantages for air pollution.

[Tim Streater]

Nothing new there.

[John Brown]

Tim Streater [e-mail] wrote

He didn?t ask about new.

[The Natural Philosopher]

I will agree with that.

Worse than what it purports to replace. leads to cold damp houses that play havoc with lungs

Same.

[John Brown]

The Natural Philosopher [e-mail] wrote

Nope.

Nope, not with a well insulated well sealed passive solar house.

Not when the house is designed properly.

Nope, not with a well insulated well sealed passive solar house.

[Andrew]

And a dehumidifier to remove any excess water vapour

[SH]

Or use a MVHR unit (Mechanical Ventilation Heat Recovery) unit.

[The Natural Philosopher]

If you had a a well insulated well sealed passive solar house. you wouldn't need to wear a jumper.

And the more well sealed it is, the more damp there is inside it

(that reminds me:I need toi go and close all the bedroom and bathroom windows I had to open because of humidity build up).

I did the calcs once. At around 6" of decent insulation the *legal* requirement to breathe fresh air makes having any more pointless. Even with heat recovery ventilation that makes it pointless at 10-12".

And that's about where the regulations are for new builds.

[Andrew]

BS as usual. Properties built to this German standard will have (or should have) an air recycling system that warms incoming air using the heat of the exhausted air.

[Martin Brown]

So your house is actually well insulated and draft proofed then?

Legal requirements for a solid fuel wood burner ventilation are a bit of a nuisance on this front too. I'm inclined to think you are right about the 6" of decent insulation although where possible in the loft I have

10" and twice that over the warmest sections of the house (determined more by the dimensions of the insulation I used than anything else).

My exterior walls and solid floor are the weak spots now. They are much more difficult to sort out without a lot of disruption or disfiguring the exterior of the building (in a conservation area).

Things that could be done more sensibly in new build are orient roofs so that they face S or SE consistently rather than towards the nearest road. Passive solar gain on the SE/S/SW sides can be impressive but to have control of summer temperatures there needs to be an overhang or blind to cast a shadow when the sun is high.

The house we had in Belgium had enormous solar gain. Far too much in midsummer - I had to add external bamboo blinds to control it. Some continental homes have sunblinds above their windows much like high street shops used to have (and some in market towns still do).

[John Brown]

The Natural Philosopher [e-mail] wrote

Depends on how well insulated it is and how big the house is and how cloudy it usually is. A superinsulated small house, sure.

Damp is easy to avoid with a dehumidifier that costs little to run in that sort of house.

A dehumidifier works a lot better in a well sealed house, particularly if you do the veg in the microwave instead of boiling it to death on the hob. I personally do frozen veg like peas and beans and rice in the microwave and the only real source of much humidity is the hot shower.

Sure, but that?s a green approach which works well when done properly with the house well sealed against leaks. Obviously a lot easier with a new house.