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darkr

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air source heat pumps, though they're improving won't do well in extreme cold; even if they can operate they'll still be running at much lower efficiency.

For temperatures significantly into negative territory a ground source heat pump would perform far better, where it can draw on a source of heat that will always be at least above freezing.

A hybrid system doesn't seem like a bad trade-off though..

The first season is a masterpiece. Second season goes off the rails and loses direction fairly early on

Similarly python in optimised mode with -O or -OO flags will disable asserts.

I see asserts as a less temporary version of print() based debugging. Sometimes very useful as a quick and dirty fix, but 9 times out of 10 you’re better off with some combination of a real debugger, unit tests, tracing/logging, and better typing or validation.

Great PR move, but surely better to invest in more basic security measures supported by their app (chain of trust, verified callers/messaging etc). Instead their app is primarily a react native sales tool. Part of the reason that o2 was so affected by scammers calling from south Asian call centres with “the latest offers” was because they used to do exactly this with their customers.

In the UK, dew point highs will peak above 22 degrees multiple times per year, so the safe temperature to cool to is something like 25 degrees.

Might provide some benefits on really hot days, but it’s still uncomfortably warm for working in.

It would only need to be 4.7 to beat a gas/oil system that is 100% efficient.

In reality, a very good gas based system that is well specified and installed might reach 80% as a whole. Most UK gas/oil heating systems are significantly lower.

WRT cooling with water based system there are a few of issues:

1. A system that also provides cooling isn’t allowed under the heat pump government grant.

2. You might actually need planning permission for this

3. Especially in a humid environment like the uk, you can end up with condensation and damp issues, which you really don’t want in an underfloor slab install

If you also want cooling, better to go an air-air based system (aka air conditioning)

Those figures are for the unit itself. It takes a lot less energy to heat air than it does to heat water, but water retains heat for much longer.

What matters is the SCOP for the system as a whole.

In a traditional Victorian house with a fireplace in every room, radiant heat will provide far greater efficiency than a forced air system, in which all of that warm air will literally go straight up the chimney.

Another issue with heat pump rollout, at least in the UK is a severe lack of qualified heating engineers with a basic understanding of thermodynamic principles.

Thus you get plumbers with experience installing gas boilers, resulting in poorly specified and installed systems that provide nowhere near the efficiency that they should reach.

This then leads people to say “heat pumps don’t work” or “heat pumps are expensive to run”, which only feeds into the whole anti net-zero rhetoric.

This. The cost of installing and upgrading a big old drafty Victorian house to a COP 4+ efficiency where the running costs actually beat oil/gas would have a break even point way past the end of my lifetime.

This doesn’t surprise me. I found an information exposure vuln on the user registration endpoint a while ago (given a phone number of an authy user who had previously registered via another customer, retrieve all other numbers/devices/timestamps, email addresses and other info for that user).

It took them two years to fix it.

Revocation for random domains is kind of a moo point as chrome doesn’t do OCSP default, just CRLsets that are pushed out with browser releases, that probably won’t include your domain.

Better instead just to have shorter TTL certs.