Heavyweight physics prof weighs into climate/energy scrap
Zero-carbon UK plans for all: Greens, nimbys, even Libs
Analysis A topflight science brainbox at Cambridge University has weighed into the ever-louder and more unruly climate/energy debate with several things that so far have been mostly lacking: hard numbers, willingness to upset all sides, and an attempt to see whether the various agendas put forward would actually stack up.
Professor David J C MacKay of the Cambridge University Department of Physics holds a PhD in computation from Cal Tech and a starred first in Physics, so we can take it that he knows his numbers. And, as he points out, numbers are typically lacking in current discussion around carbon emissions and energy use.
MacKay tells The Reg that he was first drawn into this field by the constant suggestion — from the Beeb, parts of the government etc — that we can seriously impact our personal energy consumption by doing such things as turning our TVs off standby or unplugging our mobile-phone chargers.
Anyone with even a slight grasp of energy units should know that this is madness. Skipping one bath saves a much energy as leaving your TV off standby for over six months. People who wash regularly, wear clean clothes, consume hot food or drink, use powered transport of any kind and live in warm houses have no need to worry about the energy they use to power their electronics; it’s insignificant compared to the other things.
Most of us don’t see basic hygiene, decent food and warm houses as sinful luxuries, but as things we can reasonably expect to have. This means that society as a whole needs a lot of energy, which led MacKay to consider how this might realistically be supplied in a low-carbon fashion. He’s coming at the issues from a green/ecological viewpoint, but climate-change sceptics who are nonetheless concerned about Blighty becoming dependent on Russian gas and Saudi oil — as the North Sea starts to play out — will also find his analysis interesting. Eliminating carbon largely equates to eliminating gas and oil use.
“I don’t really mind too much what your plan is,” MacKay told The Reg this week. “But it’s got to add up.”
He says he’s largely letting his machine-learning lab at Cambridge run itself these days, and is personally spending most of his time on trying out different energy scenarios.
MacKay sets out his calculations in a book, Sustainable Energy — Without the hot air. You can download it here. As he says:
The one thing I am sure of is that the answers to our sustainable energy questions will involve numbers; any sane discussion of sustainable energy requires numbers. This book’s got ’em, and it shows how to handle them.
He emphasises that the book isn’t quite finished yet, and says he’s always glad to hear from someone who has something to add or has spotted a mistake.
In Without the hot air, MacKay examines our total energy usage in the UK, and then tries to provide a similar amount of energy but without using any oil and gas. He’s willing to consider windpower on a thoroughly heroic scale, as it is probably the renewable technology best suited to the UK climate. As a benchmark for wind, he writes:
Our conclusion: if we covered the windiest 10 per cent of the country with windmills, we might be able to generate half of the energy used by driving a car 50 km per day each. Britain’s onshore wind energy resource may be “huge,” but it’s not as huge as our huge consumption. I should emphasize how audacious an assumption I’m making. … The windmills required … are fifty times the entire wind hardware of Denmark; seven times all the windfarms of Germany; and double the entire fleet of all wind turbines in the world. This conclusion – that the greatest that onshore wind could add up to, albeit ‘huge’, is much less than our consumption – is important …
Need to consider transportation fuel sector separately
Dr. Mackay has done an excellent job at a high level of assessing the possibilities for the world's future energy availability. In particular, I like his assessment of the limitation of land for biofuels and the need to go to breeder reactors if we are to use nuclear.
He has, however, made one assumption about the fungibility of energy. Until we have batteries which can efficiently and economically store energy for transportation, we need to consider the need for liquid transportation fuel (hydrogen has a need for new infrastractures and storage.and I think is a poor bet.
And so I feel the world should be looking for the interim solution of coal-to-liquid to augment oil and serve to keep price under control. Let's stop using coal for electric generation over the next several decades and use it for transportation - until we either have batteries, the algae process is developed or somebody figures out how to use solar energy, air and water to make liquid fuel.
Write to Somarl@msn.com for direct discussion..
@ Michael and anyone else that things CO2 is bad!
"(a) Switching stuff and using low energy light bulbs >does< help. In my (rather high tech) house I brought electricity consumption down by 30% by this technique at essentially no inconvenience to me. Nationally, switching to low energy bulbs means that roughly 1 GWe of installed capacity can be switched off - about 2% o fUK demand or one power station we don't need to build."
Nice to see you've replaced your normal non poluting light bulbs with ones containing lots of nasty chemicals well done there.
"(c) The authors assumed faith in clean coal is endearing. This is a technology which has never been demonstrated at scale, and the scale required is collosal. Taking world numbers of something on the order of 10 billion tonnes of CO2 per annum, this occupies a volume at a minimum 10 cubic kilometres. This volume has to be gas tight with an internal pressure of 50 bar and storage would have to be permanent. This volume would have to be built every year. For the UK the demands are proportionately less, but it makes storing nuclear waste look easy."
Oh that deadly CO2 again, you know we could just feed it to plant life I hear they quiet like it. I see your misconception that it's better we go with a really nasty polutant like nuclear waste or mercury light bulbs.
WAKE UP MAN MADE GLOBAL WARMING IS A LIE!!!!
Whats far more important is the amount of real polutants that big business pumps into our air and water supplies things like heavy metals, man made chemicals etc. CO2 is easily dealt with by more vegitation something that more CO2 actually encourages.
@Anne van der Bom again...Re: you're hot water calculation.
1. 15 to 35C. The average human is about 38C, A 35C bath, that's not hot it's tepid. The author was using 10C to 50C, that's a lot more typical, though if we want to skew the numbers I suppose we could be warming Saharan water from say a balmy 45C to 50C and save a whole lot of energy. Makes ther case better!
2. 70L. Based on a typical Canadian Bathtubs internal size (maybe Europe's different) of roughly 142cmx61cmx36cm, 70L gets me 8.1 cm of soaking glory. The author suggests larger dimensions and deeper water, again more realistic.
So the hot bath is now defined as 8cm of lukewarm water. I'd like everyone to go home and try this out tonight.
3. Now we heat it. You assume a 90% gas heater. Why? This gets around the irritating 35% generating efficiency you goose the 2W standy unit with. Nice.
Personally, When I bath I use a small bucket (10L) and limit the temperature to a balmy 25C. I like it brisk. Did I mention I have black solar coils on my thatch roof in my equatorial abode, so I'm pretty efficient.
Tongue in cheek aside, you can manipulate your numbers to make your case, and in your case I think perhaps you're being a bit generous to your case. Again, you're not being skeptical, you're agenda is obvious here. From what I've read of the paper, the author is making ballpark calculations, and it's obvious, he makes no effort to hide this. The values he chooses are general, typical, what the average person uses. Be average, it's what everyone else is, and if you base your case on anything else, your argument doesn't hold much water (hot, tepid or brisk), because it assumes the best of people, that they'll change out of the good of their heart. Perhaps you've noticed, that's not reality.