Duncan Westland
@westlad.bsky.social
It’s fine to jump out of a window because theories of gravity are never fully settled.
September 26, 2025 at 9:45 AM
It’s fine to jump out of a window because theories of gravity are never fully settled.
I wonder why CCGT is cheaper with CCS than without.
August 27, 2025 at 9:17 AM
I wonder why CCGT is cheaper with CCS than without.
How strange. I mean, a Peltier device does pump heat, but reading around, the COP in a situation like this seems way less than 2 (they seem to define COP in terms of heat extracted, rather than heat supplied) and, as you say, no way to supply enough heat to the cold side.
August 7, 2025 at 8:59 PM
How strange. I mean, a Peltier device does pump heat, but reading around, the COP in a situation like this seems way less than 2 (they seem to define COP in terms of heat extracted, rather than heat supplied) and, as you say, no way to supply enough heat to the cold side.
No, not Tesla but independent garages do. EV market is a bit further forward in the UK.
April 13, 2025 at 6:52 PM
No, not Tesla but independent garages do. EV market is a bit further forward in the UK.
You’re back on replacing batteries, aren’t you? You don’t need to do that. Cell module replacement is way cheaper, at least in the UK.
April 13, 2025 at 6:13 PM
You’re back on replacing batteries, aren’t you? You don’t need to do that. Cell module replacement is way cheaper, at least in the UK.
Well, clearly that isn’t a given because it must depend on what’s wrong with the battery.
April 13, 2025 at 5:52 PM
Well, clearly that isn’t a given because it must depend on what’s wrong with the battery.
This argument seems to rely on the premise that an HV battery cannot be repaired. This is false however. For example, Cleevely EV offer this service.
April 13, 2025 at 5:40 PM
This argument seems to rely on the premise that an HV battery cannot be repaired. This is false however. For example, Cleevely EV offer this service.
Well, let’s see. 10kW is a big heat pump. Mine is 5kW for a four bed 1958 detached. 5kW is the max rated heat output, not average electrical input. Over the last month I used 647kW hr at 9p/kWh because of batteries, so £1.87/day in the coldest part of the year. That’s what you are missing.
March 1, 2025 at 1:19 PM
Well, let’s see. 10kW is a big heat pump. Mine is 5kW for a four bed 1958 detached. 5kW is the max rated heat output, not average electrical input. Over the last month I used 647kW hr at 9p/kWh because of batteries, so £1.87/day in the coldest part of the year. That’s what you are missing.
Yes, although it doesn’t reach maximal Carnot efficiency in normal use.
February 1, 2025 at 4:15 PM
Yes, although it doesn’t reach maximal Carnot efficiency in normal use.
Personal profit is certainly a consideration, as is the type of world we wish to leave for our grandchildren.
January 27, 2025 at 6:36 PM
Personal profit is certainly a consideration, as is the type of world we wish to leave for our grandchildren.
This was great. I didn’t know about the through-wall heat recovery fans so I certainly learned something.
January 26, 2025 at 8:49 AM
This was great. I didn’t know about the through-wall heat recovery fans so I certainly learned something.
The same was reported in the Guardian but finishes with: A government spokesperson said “This story is categorically untrue. The government is working with Natural England to review options on species reintroduction, including beavers”. It’s the Daily Star so…
January 15, 2025 at 3:42 PM
The same was reported in the Guardian but finishes with: A government spokesperson said “This story is categorically untrue. The government is working with Natural England to review options on species reintroduction, including beavers”. It’s the Daily Star so…
Just a 5 minute wait a Fleet services the day after Boxing Day.
January 10, 2025 at 1:52 PM
Just a 5 minute wait a Fleet services the day after Boxing Day.
Two technology curves relate to exponentials: The learning curve (fall of technology cost over time) and the S curve (rate of adoption of new technology). Neither really predicts how our technical capabilities will change though. I think the Gartner hype curve is more relevant for current AI.
December 24, 2024 at 8:31 AM
Two technology curves relate to exponentials: The learning curve (fall of technology cost over time) and the S curve (rate of adoption of new technology). Neither really predicts how our technical capabilities will change though. I think the Gartner hype curve is more relevant for current AI.
What a good idea!
December 4, 2024 at 8:38 PM
What a good idea!
Not sure who “we” are. I’m in the UK and my heat pump works brilliantly, and is virtually inaudible.
December 4, 2024 at 8:35 PM
Not sure who “we” are. I’m in the UK and my heat pump works brilliantly, and is virtually inaudible.
This is a really well made website!
November 24, 2024 at 8:10 AM
This is a really well made website!
Oh yes, good point. I hadn’t noticed that. It was about them that I tweaked the weather compensation curve a bit higher, so that must be what did it.
November 24, 2024 at 7:45 AM
Oh yes, good point. I hadn’t noticed that. It was about them that I tweaked the weather compensation curve a bit higher, so that must be what did it.
I had similar results, although with a mean about 10% lower. The 5kW Arotherm+ is completely maxed out here.
November 23, 2024 at 3:23 PM
I had similar results, although with a mean about 10% lower. The 5kW Arotherm+ is completely maxed out here.
It’s often said, but never evidenced.
November 17, 2024 at 9:35 AM
It’s often said, but never evidenced.
I enjoyed this thoughtful essay.
November 17, 2024 at 9:30 AM
I enjoyed this thoughtful essay.