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Comment: Re:Waste is heat! (Score 1) 187

Yes it is, because you are wasting lots of extra exergy, ie you could be getting the heat you need with far less electricity, leaving the rest for someone else or allowing less upstream resource (nuclear fuel, water, transmission infrastructure) to be consumed for the same outcome.

Rgds

Damon

Comment: Re: What Would be a Trivial Amount? (Score 1) 187

Indeed. We should be targetting microwatts or at most tens of milliwatts not tens of watts. We're talking lazy engineering and insufficiently discerning end-users here.

(I'd like to chat about your stuff off-line, BTW. as part of our public IoT Launchpad project, see sig!)

Rgds

Damon

Comment: Re:QuikClot and Celox (Score 3, Interesting) 71

by DamonHD (#49364213) Attached to: Material Made From Crustaceans Could Combat Battlefield Blood Loss

Is there a significant antigen left in this foam?

I know people can be allergic to almost anything, but this looks to me like only relatively simple innocuous compounds remain in the foam.

The point being on the battlefield, what proportion of people would be killed by this from anaphylaxis (say) rather than saved by it?

Rgds

Damon

Comment: Re:EU regs state standby power must use 0.5W (Score 2) 187

IIRC units are shipped in the EU with the 'instant-on' mode disabled by default, which would meet regs.

So it's superficially a software issue pandering to a chunk of their consumers being by default happy to waste lots of energy all the time (or never realising what's going on) rather than press a button. And we wonder why some places have an obesity and a power-consumption problem!

Rgds

Damon

Comment: Re:EU regs state standby power must use 0.5W (Score 1) 187

1) I thought that the EU limit was now 0.1W.

2) I think that if the manufacturers don't call the mode 'standby' then they may be able to draw what power they like: cue unholy mix of engineers and marketing bods gaming the regs with euphemisms...

Rgds

Damon

Comment: Re:Waste is heat! (Score 1) 187

And electric resistance heating is usually *terrible* compared to any number of available alternatives.

It represents a *huge* waste of exergy, when a heat pump (as you allude to) can produce several units of heat for one unit of electricity.

So, in summer it's all bad and in winter it;'s at least 75% bad. And that's ignoring (eg) CO2 and other emissions from the generation mix.

Can we stop with this "waste is good" meme?

Rgds

Damon

Comment: Re:Power supply costs, BMs and shi5 (Score 1) 187

It's still not a good reason to waste something that is trivially easy to avoid wasting.

So, 0.26W would be somewhat over 0.1% of my house's mean grid consumption (1700kWh gross ignoring my solar PV). I have a family of four.

I still make an effort to charge devices off grid because it helps me think about my energy use for the bigger items too.

tl;dr: an efficient charger not doing anything isn't a killer, but 900kWh/month is a travesty.

Rgds

Damon

Comment: Re: What Would be a Trivial Amount? (Score 1) 187

Note: skylights are poor thermally and let a lot of heat out. Also I had one in a previous house in the bathroom where the seal was so bad (thus clearly leaking air too) that I had the surreal experience of being hailed on in the bath.

Also, have skylights ways from south (if you're in the northern hemisphere) to avoid excessive glare and overheating.

BTW, I have triple glazing now! Overall heat consumption from natural gas was 3000kWh last year and electricity 1700kWh.

http://www.earth.org.uk/saving...

Rgds

Damon

Comment: Re: What Would be a Trivial Amount? (Score 2) 187

EU regulations require appliances in actual standby to use no more than 0.1W, which is less than a neon indicator bulb, and *is* good.

My cable TV box uses 15W and consequently I make sure that it is turned off completely, along with TV and DVD else it would be responsible for ~10W of our entire electricity bill.

http://www.earth.org.uk/saving...

I have prototype voice detection circuit sitting on my bend that is using tens of microwatts to detect occupancy, so milliwatts should be plenty to do the instant-on job for those too damn idle to press a button.

tl;dr: 10W is *crap* for an always-on device doing nothing.

Rgds

Damon

To err is human -- to blame it on a computer is even more so.

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