Ken Neil states:
If you're talking about the same design house, I can't see why a 55kW house using pellets and ST should emit more CO2. There must be a flaw in their methodology there. It does not compute!!
I do not understand what this means: a 55kW house emitting more CO2 than what?
They haven't compared a PassivHaus using the same pellets and ST as the 55 and 75kw houses.
That is correct. The CO2 emissions from a similar PH equipped with pellet heating (DHW and space heating) would be even worse.
The heating system's usage would be much less due to the low demand of thermal energy of the PH, it's life time expectation the same.
Don't forget that everything has an end. Insulation, boilers and stoves. These things need maintenance and replacement, otherwise the entire structure becomes useless.
The entire CO2 balance has to be taken into account, all works, all materials. Purchased equipment has to work, has to perform as much as possible. Idle machinery is dead capital, is expensive.
A PH with pellet boiler and ST system costs more than a PH with gas boiler. Or direct electric heating.
Get your economics straight.
We have had similar discussions about the durability of external wall insulation, check the previous threads.
In my experience this type of insulation can last but can fail as well.
1 EWI job failure destroys the calculated energy and CO2 balance sheet of hundreds of non-failures. Nothing is gained in such a case. Think globaly.
To use different investment failure samples:
Arms can protect against wild animals, but most arms are used against people. Humanity's arms handling balance sheet is negative. Same goes for car usage and so on.
As said: check the previous threads, there are many samples listed where investments in EWI have failed due to rot, decay,fire and an endless maintenance scheme. Became life threatening risks. Asbestos, mineral fibres, fungal spores, fire retardents, anti-biotics ....
Sure the insulation industry ( many billions of dollars/pounds/euros heavy ) can provide us with a similar study? Showing a CO2/energy balance sheet based on total calculations?
They would be shooting into their own foot like the arms industry, hence nothing the like they show.
Fraunhofer society, the IEA, ECOFIS and Sarazin bank have much more detailed studies done on this type of research. The outcome was always the same: a total energy balance sheet/CO2 balance sheet asks for electric heated tents as the most "green" form of housing.
The more we move away from the absolute minimum of a protective structure the more capital is needed. In a capitalistic society there are victims of capital aglomeration. The more money is gathered the more victims there will be.
The higher the expenditures on buildings are the more negative their energy balance sheets become.
A simple economical fact which does not have to be discussed - I think.
The use of a 40 year design life to compare costs is just plain stupid.
That's correct. The Germans calculate 30 years of life time expectation per EWI treated building, those who try to sell them with a guaranteed performance of more than 30 years are called " plain stupid ". And those who buy such marketing slogans as well.
After this: demolition, new job with new prices. Nothing is saved, only the builders,banks and manufacturers profit.
There are many EWI structures which last longer. But there are also many which last shorter.
The life time expectation for plastic foams used for EWI is 30 years, PH or not.
There are more expensive materials and EWI insulation methods like foamed concrete and foamed glas. These materials don't rot, don't burn, don't leach out fungizides and algicides and other biozides, last as long as the bricks. But usage of these materials asks as well for a higher price, a longer pay-back period as well. Longer than the original buyer's life time/economical part taking in our society is expected.
If someone has other studies available on the insulation issue (looking at the total energy balance/CO2 equivalents) then publish them.
About the glass panes:
The life time expectation for cheap gas filled dubble glazing is 10 years. No manufacturer gives more than 10 years on the performance. Only very few manufacturers do so - for an extra charge of course.
And this for a very good reason: This 10 year performance guarantee drives the price per pane up by 100% compared to the normal 2 year guarantee.
And that is the principle of all insulants, the better they are (life time expectation) the more they cost.
Performance guarantees for solar equipment ? 25 years.
A ST/PV combi panel with a 10 year performance guarantee is already cheaper than a triple glazing pane of the same size with a 2 year guarantee. Insulating better and
gaining more energy for the building.
Wasting building surfaces to clutter them with insulants is bad building practice. Very wastefull, very bad for the planet and the home owner's pocket.
There is a very good reason why building regulations have to force
thermal insulation on to homeowners/-builders. Since the economics don't ad up. Otherwise the market would ask for more thermal insulation without being forced by law.
Well, that's the official position of the German home owner association. They have studied the issue as well.
Would you like to read their statements?
The commonly used term for this economical insulation madness in Germany is "Daemmwahn", check google or the like. Is there a similar British term?
What is the official position of the British home owner association? The British consumer organisation?