Sunday, 21 July 2013

Fwd: Power-Hungry Devices Use $70 Billion of Energy Annually

Here's the kind of fun story that gives us pause.

I got some ice cream yesterday from what is probably the best ice cream shop in the world (come to Matsumoto and taste it if you don't believe me). I took a small cooler box so I could put the stuff straight in there, along with some of the dry ice they provide for free. But they insisted on wrapping it in some expanded plastic sheet. I was tempted to take the ice cream and the dry ice out of the sheet, put them in the cooler box, and put the sheet back on the counter. In the end I just took the package they had made and put it in the cooler box.

I mean, if I was so worried about reducing excess resource use, what on earth was I doing getting ice cream?

How much energy is used freezing and keeping the produce frozen? Already there's a calorific calamity because many times more fossil fuel energy is used growing and transporting food than is contained in the food itself.

And dry ice is frozen carbon dioxide. Isn't that great that they're taking CO2 out of the atmosphere? Well actually it goes straight back into the atmosphere when it sublimes. The CO2 was probably made as a biproduct of some process and was not made specially. An estimate from ASCO inc's dry ice machine B207's spec suggests the manufacture of a kg of dry ice uses around 100 watt hours of electricity, in turn putting around 50 grammes of CO2 into the atmosphere, which is actually much less than I expected. Interestingly, this is similar to the production of regular H2O ice, but a kg of dry ice has twice the cooling capacity of wet ice. Not as good in drinks though. And more dangerous.

Anyway, after the fertilizers on the fields, the trucks, ships and planes speeding produce around the world, the freezers making the ice cream, and chilled cabinets displaying it, a little bit of extra plastic wrapping is not going to make a huge difference.  But that's not what I really wanted to talk about.

Back to the US and their profligate use of energy, "A new analysis of devices and equipment commonly found in U.S. homes and businesses concludes that these products, with more than 2 billion in use, consume more energy each year than many large countries use to power their entire economies."

They're talking about TVs, computers, ceiling fans, elevators, icemakers, and MRI machines. They use "more than the primary energy use of Mexico, Australia, New Zealand, or 200 other countries."

You can read the full report from American Council for an Energy-Efficient Economy (ACEEE) here:

Of course they are advocating energy efficiency, and state "these devices could be made to use 40-50 percent less energy with existing technology."

Because these devices "do not fit into traditional energy-use categories such as refrigeration, HVAC, or lighting" they seem to be off the radar. They are not subject to energy efficiency requirements, and efficiency standards are unevenly applied.

More obviously, not having the devices in the first place is going to use much less energy than any energy efficiency improvements. Energy efficiency gains are usually incremental, and often start from very low levels. The first steam trains converted a fraction of one percent of the coal's energy into motion. This was worth it because the economics of the day made this cheaper than driving horses to the pit heads.

Escaltors are a good example. Many of them have sensors and will stop when nobody is riding. Of course the point of escalators is often to transport people up and away to the higher levels of a shop, where they will spend more money and keep the cash tills ringing. The lights will keep everything bright, the heaters keep the rooms warm and the refrigerators keep produce cold. A moving escalator is a powerful symbol of this motion, as well as a delivery system for these life-supported wallets.

In terms of delivering a payload, namely human beings, the weight of the metal is going to make a huge difference to the efficiency. How does this compare with a lift? I imagine a whole lot less friction and more effiency for a lift, in terms of energy use, but perhaps not in terms of space use, constant movement of human traffic, and incidental advertising of shops and products that can be seen on the way. But how does this compare with the energy that would have been used if the customers had walked? In these terms, much less efficient, unless of course that energy came from ice cream.