Tag Archives: energy

The Christmas Lights Fallacy

Just twenty years ago, there was a popular factoid doing the rounds:

Half of the world’s population have never used a telephone.

I was working on technology for the developing world at the time, and this came up occasionally at conferences and other discussions. It was repeated by Kofi Annan, Al Gore, Belinda Gates, Newt Gingrich…. It was one of those facts that was shocking enough to be interesting, but believable enough to make you think of the implications. You may think you’re in the midst of the dot-com boom, but remember that half the world has never even made a phone call…

But, as I blogged at the time, Clay Shirky went and did some research, and found that, actually, the statistic was first used in 1994, and, even if it had been true then, it certainly wasn’t by the time everyone was quoting it in the early 2000s. Seven years, it turned out, was a very long time in technology.

I was thinking of this today as I read Charles Arthur’s nice analysis of another recent assertion: that Bitcoin may use a lot of energy, but not as much as everybody’s Christmas lights! It’s a fun fact to surprise your friends with at the pub, perhaps, but, as Charles found out, it’s not quite grounded in reality. Take a look.

Sometimes it’s very good to have proper journalists around.

Watt’s the cost?

A few years ago, I came across a really useful rule-of-thumb for calculating electricity cost:

A 1-watt device costs £1/year, if it’s running 24×7.

At the time, this was almost exactly right for most people in the UK, and it made it very easy to estimate the impact of, say, using that old 200W PC as a server for the next three years rather than getting a more modern low-power one.

Sadly, for most of us, energy costs are going up a lot at the moment, and the above is probably rather optimistic now, so you might want to do the calculation for yourself. For example, I currently have a big Synology NAS server here at home storing lots of my data and backups. Once you’ve bought such a device, how do the running costs compare with storing your data in the cloud?

So here’s my exciting new highly-sophisticated web application, which is designed to answer this simple question:

Watt’s The Cost?

Hot at the top

This is a lovely idea – the Mixergy hot water tank.

A standard UK hot water tank heats the water from the bottom, either using electricity or water heated by a gas boiler. This means that when you want to heat up your water, you need to heat the whole thing.

Mixergy, instead, put the heating at the top, so you can warm up smaller amounts of water, and then make intelligent use of pumps to circulate it as required if you need to heat larger amounts of water. Not only is this more energy-efficient, but it means you get hot water again more quickly after you’ve used it up.

There’s a more detailed discussion on a recent episode of Fully Charged.

Change the world with your DVD drive?

Researchers at UCLA produced graphene supercapacitors — an amazingly efficient electricity-storage medium — using a standard DVD burner.

“The process is straightforward, cost-effective and can be done at home,” El-Kady said. “One only needs a DVD burner and graphite oxide dispersion in water, which is commercially available at a moderate cost.”

More info here.

Smart Energy – now it’s personal

PilgrimMy pal Pilgrim Beart gave a splendid talk at the IET last week, about smart energy monitoring.

Click here to watch the webcast.

45 mins of talk, 45 mins of questions. Well worth the time.

All I want is a room somewhere, far away from the cold night air…

The very pretty Nest thermostat has justifiably attracted a certain amount of attention recently. But it has a few failings, too:

  • It’s expensive – someone quipped that the Apple-inspired design comes with Apple-inspired prices
  • It’s a single point of temperature measurement, and what most houses need is multiple thermostats, or at least sensors
  • It isn’t available in the UK and wouldn’t work with most UK heating systems anyway,

So, it’s not for me. But I am keen to upgrade my heating controls: we have pretty substantial fuel bills even for our small and fairly well-insulated house.

So I’m after recommendations. Here’s my ideal system:

  • You could set the temperature you want in each room, and control the times of day at which you want it. Or, even better, it would learn the pattern for each room. (And not get too confused by daylight savings time changes)
  • We have radiators in each room, so it would need to manage the radiator valves. (i.e. replace the TRVs)
  • The temperature sensors would not necessarily be on the radiator valves, but could be elsewhere in the room.
  • The timing of the boiler ignition would be based on the combined needs of the house, and not on the temperature of a particular thermostat in the hall, or of the time programmed into a separate heating controller.
  • Ideally, it could be programmed through a wife-friendly app or web interface.

Anyone know of anything that satisfies a significant number of these?  I don’t expect to get them all. But I also don’t want to spend a lot of money and time on a system which does some of them, only to discover that another would have been a better choice.
 
Oh, and I’d rather not have to do any major plumbing…

Any suggestions welcome!

© Copyright Quentin Stafford-Fraser