On 04/01/2017 08:46, Rod Speed wrote:


"RJH" wrote in message
news
On 04/01/2017 02:56, wrote:
On Wednesday, 4 January 2017 00:12:19 UTC, TimW wrote:
On 03/01/17 23:03, tabbypurr wrote:
On Tuesday, 3 January 2017 22:23:19 UTC, dennis@home wrote:

http://www.bbc.co.uk/news/business-38391034

A carbon capture plant that takes CO2 from the coal fired plant and
makes baking powder.

So what do they do with the baking powder..

they bake with it releasing the CO2.

Yet this is green and reduces CO2 emissions!

Carbon capture has never made any sense even at the most basic
level. But if it can rake in subsidies...

How could it not make sense?
I understand a method and technology has been elusive, but itmakes
sense
at a basic level to take CO2 out of the atmosphere, no?
TW

Energy generation requires turning C into CO2 to generate heat. Going
from CO2 back to any less oxidised form is merely reversing the
process. It's like taking 2 steps forward then one back, you make
less progress. And since the step back costs money and is not
entirely efficient, the whole process ends up using more energy per
kWh out, producing more CO2 per kWh out, and costing more. It just
fails to make any sense.

I've read a few articles now from the peer reviewed scientific press
on the environmental impact of insulation materials.

While useful and doubtless scholarly (on my lay reading) in the sense
of seeing which materials work, in what quantity and why, reported
wider environmental benefits are misleading.

Nope.

Not a single one even mentions the 'CO2 cost' of production, only
effects post-fit -

That's because the CO2 cost of the production of the
insulation is a trivial part of the dramatic reduction
in the CO2 produced when heating the place.


Well, a very rough calculation taking my house and insulating just
floors and roof with Celotex would suggest that it would take about 5
years to offset the CO2 used in the manufacture of the insulation
material (Celotex 160kgCO2e/m3, gas 0.2kg/kW/hr). And factor in building
life, installation errors, use, ventilation - I find the science just
lacking.

It obviously gets more complicated with walls - payback may be quicker
due to high heat loss.

Worth it in the long haul, but not trivial. Especially to those who do
things for 'green' reasons - the papers I've read are environmentally
inclined.

Money saved is a different matter - depends a great deal on installation
costs. Far and away the best value thing I've done here - two alcoves,
about a day, less than £100. But it'd still take some yeasr to repay the
materials costs.


--
Cheers, Rob