4

Interesting Ideas from George Monbiot

Here is a transcript of a lecture by George Monbiot about climate change and what we need to do. The latest scientific evidence suggests that we need to cut emissions to zero by 2030 to avoid significant increases in the sea level over the next century, George describes some options that will form part of a solution to this problem. Below are my comments on what I consider the most interesting (the ideas that I hadn’t heard of before), I recommend reading the full article for the rest.

  1. Have a carbon ration for each citizen. Wealthy people who want to use more resources could buy carbon rations from poorer people on an open market. That way people who use less than their ration still have an incentive to save more because the extra savings are worth money! As everyone would then have a financial incentive to reduce emissions there would be a lot of new development of methods and technologies for eliminating or compensating for carbon emissions, capitalism works!
  2. Build battery powered cars with interchangeable batteries. The idea is that you rent a battery from a fuel company, and whenever it runs low you go to a service station and swap it for a fully charged battery (for a small fee). If doing this the service station could use cheap night-time electricity to charge the batteries, and the batteries that are charged could be used to put electricity back into the grid at times of peak demand. A common idea is to have Prius+ type vehicles charge from the grid when not being used and then sell electricity back to the grid at peak times. Implementing such a system for millions of homes is technically challenging and expensive. But having a much smaller number of service stations sell larger quantities of electricity back to the grid is easier to manage.
  3. Reduce air travel by 90%. I wonder how much of this can be achieved by using high-speed trains for all national travel systems and for most travel within the EU. I have often travelled between Amsterdam and London by train, it’s much more civilised than flying.
  4. Classic quote from George on John Howard: “if Howard believes a slight reduction in consumption is a recessionary measure he ought to see what a total reduction of land area would be as a result of the melting of the west Antarctic ice sheet. The two things are just completely out of proportion..”

George Monbiot also has recently released a new book Heat: How to Stop the Planet from Burning.

4

The Silly BMW 745h

BMW has released a new prototype hydrogen powered car. The bmwworld.com web page about it claims the cruising range is 190 miles. Added to the 400-mile range of the normal fuel tank, the 745h can go 600 miles between fill-ups. The first issue is that 10 miles are not accounted for (maybe it finishes the 190 miles of hydrogen power at the top of a hill). But more seriously the hydrogen needed to drive for 190 miles would take as much space as petrol needed to drive for 646 miles (hydrogen needs 3.4* the volume to store an equivalent amount of energy). I wonder if that BMW has any space left in the boot/trunk?

Now we have some green bloggers praising BMW. An internal combustion engine that burns hydrogen will not give no emissions other than water vapour, it will produce some nitrogen oxides. The processes to produce hydrogen for fuel all consume unreasonable amounts of energy (more than is required to charge a plug-in hybrid).

BMW demonstrates their level of interest by giving the cars to some celebrities. This gets some PR but no analysis of the performance. They also introduce the prototype based on one of the most expensive models (the 745) which you almost never see on the roads. If they produced a 318 or 520 that ran on hydrogen it would demonstrate some level of interest in getting this working for the mass market.

If BMW wanted to make their cars more environmentally friendly they would start by adopting some of the technology from the Prius. Rumour has it that part of Toyota’s plan to make money from Prius development is in licensing the technology that they patent. A couple of years ago I test drove a BMW 316 and a Prius. The Prius was very quiet and gave a smooth ride (you might call these luxury features), and also gave decent performance (it’s widely regarded that luxury cars should perform well – pity the BMW 316 is a slug).

In Australia the concept of “badge engineering” of cars is well established. When government subsidies favoured large manufacturing runs the Ford Laser and Mazda 323 were essentially the same car. Maybe BMW could adopt this concept and sell a re-badged Prius i-tech with a few extra luxury features as a BMW 4 series (it’s a much better car than the 3 series BMW).

Finally bmwworld.com has an amusing FAQ about hydrogen power, here are some of the mistakes that they make:

  1. They say “About 45 billion kilograms (50 million tons) [of hydrogen] is produced every year—enough hydrogen to fuel 250 million fuel cell cars“, but only if the average fuel-cell car uses 180Kg of fuel per year. According to Wikipedia hydrogen has slightly more than 3* the energy density per mass than petrol, so 180Kg of fuel would be equivalent to 540L of petrol per year. The Australian Bureau of Statistics states that in 1996 the average annual distance travelled by car (it’s not clear whether this is per car or per person) was 14,600Km while among the countries listed the lowest was Japan with 10,130. When efficiently using hydrogen in a Prius (that is quoted as using 5.4L of petrol per 100Km) you might expect that 540/5.4*100=10,000Km could be travelled on the 180Kg of hydrogen. So the FAQ claim that 250M cars could be powered by the current hydrogen production would only apply if the cars are of Prius efficiency and driven the typical distances of Japanese drivers, or the cars were 46% more efficient than the Prius and driven in the Australian manner. Of course in the US things are even worse with 17,862Km being the average distance driven which means that their hypothetical fuel-cell car would need to be 78% more efficient than a Prius.
  2. They state that “the majority of merchant hydrogen is produced by a process called steam methane reforming“. Why not just run cars on methane then? Anything that burns can be used to fuel cars, and methane has a much higher boiling point than hydrogen so it would be easier to store and transport (see the Wikipedia page on methane).
  3. In regard to hydrogen production they say “about 95% of the total global hydrogen production is captive meaning it is used at the site where it is produced“, that is of course because it’s difficult and expensive to transport hydrogen.
  4. The final amusing fact is that it is noted that most hydrogen comes from fossil-fuels. What problem are they trying to solve here? Hydrogen isn’t going to help the environment if it comes from fossil fuels, it will be more expensive than other fuels. Apart from getting government grant money for BMW it doesn’t seem to do any good.
82

Hydrogen Powered Cars Will Never Work

One of the most important issues for a commodity fuel for vehicles is that it be convenient and safe to transport. For quite a while LP Gas has been available as a cheaper car fuel. Even with increasing petrol prices it’s acceptance is well below 100% due to extra expense in storing the fuel (high pressure and more insulation are required), the more expensive technology in the engine to heat the fuel before injecting it into the engine, and the extreme difficulty in creating something as convenient as a Jerry Can for transporting LPG.

LPG is mostly comprised of Propane and Butane. Propane has the lower boiling point of -42.09C. Hydrogen however has a boiling point of -252.87C and therefore is much more difficult to store and transport.

The next problem with hydrogen as a fuel is that it has a very low density. The energy density per volume of liquid hydrogen is 10.1MJ/L while the energy density of petrol/gasoline is 34.6MJ/L. Not only is liquid hydrogen difficult to transport but the vessels you transport it in need to be 3.4 times the size! Having a 3.4x larger fuel tank in a car may not be a huge obstacle, but then there is the issue of trucks used to transport it to fuel stations which are already at maximum size so the truck fleet will need to be 3.4x larger with more people driving them etc.

Once these problems are solved there are a variety of safety issues. Hydrogen burns with an almost invisible flame, sustains a fire when at a concentration of between 4% and 75% of the air and ignites at a low temperature. For an explosion you need a concentration of between 18.3% and 59%. I won’t risk promoting foolish behaviour by describing details, but when younger I have performed experiments with ethanol and witnessed experiments with petrol that demonstrate that they are both far less dangerous. Page 22 of this document by the US Bureau of Transportation and Statistics gives more information about the fire risks posed by hydrogen fuel. Page 35 of the same document describes fuel cells as being 45% efficient and an internal combustion engine for methane gas as being 30% efficient thus giving overall efficiencies of 33% and 29.5% respectively. Of course using an Atkinson Cycle engine will give a significant efficiency benefit over an Otto Cycle engine and outweigh this. Also it should be noted that fuel cells tend to require expensive materials such as Platinum in their manufacture.

Hydrogen is promoted by clean-coal advocates (not that any form of coal power is clean) and the nuclear industry (electrolysis is one way of using a huge amount of electricity). But there are many better options for powering cars that are available right now at minimal cost, these include bio-Diesel, ethanol, and plug-in hybrid or electric vehicles.

3

Solar Hot Water – Not Expensive

The Australian has a new Environment writer named Matthew Warren who has a history of doing PR work for the coal industry. This has the potential for insightful articles based on knowledge of what the industry is doing or for PR work for the coal industry masquerading as journalism. Unfortunately it seems like the latter is what we are getting.

Matthew’s latest effort is an article claiming a $6.5 billion cost to home-owners because of an “effective ban” on electric hot water systems that Labor might impose. Unfortunately he doesn’t clearly state what an effective ban is, but does note that apartments are exempt.

The specific claim that is used as the basis for the article is that solar hot-water systems cost $2,800 more than electric systems, and that after the solar hot-water rebate ($1,000) the additional cost would be $650,000,000 per annum, and that a period of 10 years would be required to replace all hot-water systems thus giving a cost of $6,500,000,000. So I presume that he expects that there would be 650,000,000/1,800 hot water systems installed per year which would be about 361,111.

According to the Australian Bureau of Statistics there were 6,744,800 households in Australia in 2003. Matthew’s article states that about 40% of homes can have gas hot-water systems fitted that comply with the proposed new regulations, given that and the exemption for apartment buildings let’s assume for the sake of discussion that 50% of homes would require a solar hot-water system. Assuming that each household has a separate hot-water system that means that for these claims to hole we need an average expected lifetime for a hot water system of 6,744,800/2/361,111 = about 9.3 years. If the currently installed hot-water systems are expected to be replaced in 9.3 years then we can expect that hot water systems tend to survive for an average of about 18.6 years. I wonder if that number is correct (some google searching didn’t turn up an answer). One of the disadvantages of old-fashioned media is that they tend not to include calculations or cite sources adequately so we can’t easily verify or disprove their claims, I wonder if this is deliberate…

Matthew admits that using a solar hot water system can be expected to save households $300 per annum in electricity expenses, I presume that this is based on current energy prices and that the savings can therefore be expected to increase as energy prices increase (we have a lack of water which is increasing the cost of producing electricity from coal).

Let’s assume for the sake of discussion that the typical home-owner has a mortgage, the Commonwealth Bank is currently advertising mortgages with a rate of just over 8%, the way things work is that there are various criteria for getting a discount rate which most borrowers can meet so the result will be slightly below 8%. If a solar hot water system costs $1,800 extra to install and the money comes from a mortgage then every year it will cost the home owner about 8% of $1,800 which is about $144 (a saving of $156 per annum). If the solar hot water system saves the home owner $300 per annum then at any interest rate below 300/1800 (16.66%) they will make money.

If there was no government subsidy and the entire $2,800 extra was paid by the home owner then at 8% interest it will cost $224 per annum (a saving of $76 per annum) and the interest rate would need to increase to 300/2800 = 10.7% to make it break even.

So for solar hot water to not save the home-owner money we need to have a significant increase in interest rates (which incidentally would bankrupt many home owners), AND to have electricity prices remain the same (which would require even more of our tax money to be spent on supporting the coal industry).

Finally Matthew complains that the solar hot-water rebate could cost the government $4 billion over the course of the scheme (the next 10 years). This sounds like a lot of money until you think about the 9 billion dollars a year that the government spends on subsidies for the coal, oil, and gas industries! On the current course the government would spend 90 billion dollars of our tax money subsidising polluting industries that cause climate change, but Matthew opposes spending 4 billion subsidising technology that prevents pollution and reduces climate change.

8

Base Load Solar Power

A frequent criticism of solar power is that the sun only shines brightly for part of the day, and that many of the times when there is significant electrical load (EG when people get home from work in winter) the sun light will be weak. One interesting solution to this problem is to store the solar power by splitting ammonia into nitrogen and hydrogen gases, storing them separately, and then reacting them to produce super-heated steam for power generation at any time that power is needed. The technology is based on three decades of research at ANU and the Federal government has allocated $7,400,000 for building a power station near Whyalla in South Australia.

The down-side to this is that it needs water for the steam part of the electricity generation process which is a minor problem as we are having water shortages in most parts of Australia. But the up-side is that the process of combining nitrogen and hydrogen to produce heat should be something that can be turned on rapidly. So it seems that there is potential for having a wind power plant designed to satisfy all the power requirements on windy days and store hydrogen and nitrogen for times when there the combination of sunlight and wind is not adequate to satisfy the power requirements.

Previous plans for the maximum possible use of renewable energy in producing electricity have included gas fired power plants for times when wind and solar power can’t meet the demand. It seems that with technology such as this one it will be practical to have all electricity produced from renewable sources of energy.

2

Water Prices and Scarcity

Due to climate change and population increases we are having increasing problems with the water supply in Australia. Peter Lieverdink suggests that we have more options for water supply including treated sewage similar to the Netherlands here he grew up. However I believe that in Australia we already do what he proposes (put treated sewage in rivers and then use the same rivers for the water supply). It’s just removing the middle step (of having the treated sewage in a river) that is controversial.

I recently examined a water bill for my house. Among other things it said that my water use was slightly above the average for houses that use water efficiently and significantly below the average for typical water use. The funny thing was that most of the expenses on the bill were not actually related to the amount of water used. My bill for a quarter was $54 service charges for sewerage and water (of which $39 was sewerage), $30 for sewage disposal, $26 for water, and $14 for drainage. So the cost of disposing of sewage was greater than the cost of getting fresh water and the sewerage service charge was the largest single item on the bill.

Australia supposedly has a capitalist economic system in place (except for the communist policies related to farming and the protection of some industries such as car manufacture and coal mining). Surely the right thing to do is to make water expensive enough that people have a financial incentive to conserve it!

The first thing that should be done is to make the majority of the value of a water bill received by a typical household be determined by the amount of water used. This could be achieved by reducing the fixed components of the bill to something small (EG $20 per quarter instead of $98 for me) and then increasing the cost per kilo-litre (EG from $0.85 to $2.50). The end result would be that people who use average amounts of water would pay about the same amount as they do now and people who use less than the average amount would get smaller bills, while government revenue would remain the same.

The next thing to do is to have different tarriffs for different quantities of water used. The first 50L per day could be free (water for drinking and cooking is a right), between 50 and 450L per day (451L per day being regarded as efficient water use for a house with four occupants and a medium garden) could be at slightly more than current prices, and usage greater than 450L per day could be significantly more expensive.

The current situation is that everyone is going to pay through taxes for desalination plants and other expensive methods of producing new fresh water. Having people pay for what they use is the capitalist way.

7

LED Headlights in Audi Sports Car

It’s interesting to see that Audi is releasing a car with LEDs for all lights including the headlights. This is being promoted as an environmental benefit, however a quick google search revealed that my Volkswagen Passat apparently takes 55W headlights (giving a total of 110W of electricity used). Even allowing for some inefficiency in the alternator this would make a very small impact on the fuel use of a engine rated at 140KW. The Audi in question is the R8 (wikipedia link because the Audi web site is badly broken) and has a 300KW engine…

A simple implementation of LED headlights will do some good for plug-in hybrid cars and all-electric vehicles where saving power is more important – when the technology filters down to cheaper vehicles. Also one possible use for the technology is to dim the headlights by turning off some of the LEDs in the bank (according to the LED Wikipedia page it is currently impossible to create a single LED that takes more than 1W of power, so a bank of LEDs would be used). Currently you have a choice of using “parking lights” or “head-lights” when driving, and when driving just before sun-set or at night in the city (where the street lights are bright) you need head-lights to allow other drivers to clearly see you but don’t need them as bright as they have to be when driving at night in the country. So a range of levels of luminosity could be effectively used in headlights to increase efficiency in some situations and increase light levels in others.

According to the Luminous efficiency Wikipedia page current LEDs are up to three times as efficient as quartz halogen incandescent globes and future developments are likely to increase that to six times the efficiency. Combine that with more effective use of headlights to provide the light at the location and level that’s needed and the result could be using at little as 10% of the electricity for headlights on average!

Another thing that I would like to see is the Adaptive Headlights feature of the better BMWs (which I referenced in a previous post about the BM 5 and 7 series) implemented in a cheaper and more reliable manner. The feature in question is that the headlights will turn when driving around a corner to show the road ahead instead of just shining off the edge of the corner. Implementing such a feature with incandescent lights is difficult because they have to be physically turned and moving parts tend to break (which increases maintenance costs and decreases the overall reliability of the vehicle). An obvious alternate design is to have a set of LEDs pointing in different directions and which LEDs get power would determine where the light goes (this would also react faster than physically moving a light). Once LED headlights become common the Adaptive Headlights feature could be implemented in the cheapest cars on the road with minimal extra cost – currently it’s a feature that would be expensive to implement and would increase the sale price of a small car and probably the service price too.

10

Germany Leads the World in Solar Power

boston.com reports that Germany now has 55% of the world’s photo-Voltaic (PV) power generation.

The German solar power industry has created tens of thousands of jobs including significant exports – so much for the Australian government claims that supporting the dirty coal industry is necessary for the economy! The renewable power industry in Germany employs over 250,000 people.

Australia has much more sun-light than Germany, the same programs of creating solar power could give better results here!

16

Hot Water

A response to a post I wrote about things to do for the environment suggested that there would be a health risk to lowering the temperature of a home hot-water system to save power.

I have just been reading about so-called tankless hot-water systems. The concept is that instead of keeping a tank of water hot (which means that you lose some energy due to the insulation not being perfect) you heat water when you need it. The down-side to this is that you need a moderate amount of power to heat water as rapidly as it’s used. The GoTankless.com products use between 11KW and 27KW of electricity. The early implementations of this idea used gas – the occasional carbon-monoxide problem with gas appliances makes me inclined to avoid them so it’s good that there’s an electric option.

One of the benefits of the tankless system is that it runs the water at a lower temperature than a regular hot water system. For a tank storing hot water you have to run it at a temperature that kills bacteria (or at least dramatically inhibits their growth) – which means greater than 50C, but for on-demand water it’s safer to have it run at something close to the desired temperature (probably not much above 40C) and not use the cold tap. Lower temperature water avoids the risk of scalding for children and the elderly and if the “hot tap” is running at a good temperature for a shower then you can just turn it on, wait 30 seconds for the pipes to warm up, and jump in! Incidentally it really sucks the way most showers have the taps under or behind the flow of water, so if the water becomes too hot before you get in then you end up getting minor burns in the process of turning on the cold tap.

I still think that solar hot water is the way to go. It apparently combines something like a tankless system on water that comes out of a tank heated by the sun. So during winter it operates like a tankless system but in summer you get more hot water than you can use.

This web site about Solar hot water systems indicates that they have a similar technology to “boost” solar hot water, so if the Sun doesn’t make the water hot enough then it can use electric or gas systems to further heat the water. It’s also interesting to note that they offer Heat Pump hot-water systems, it’s a pity that they apparently don’t support combining this with solar heating. Another interesting feature is what they call the Water Guardian that pumps cold water from the pipes back into the water tank and avoids wasting the water that you might otherwise run down the sink while waiting for it to get hot.

5

Train Routing

Last year I spent several months living on one side of Melbourne and working on the other and travelling by train to work. Every day I had to catch two trains each way with an average wait of 5 to 10 minutes for each train to arrive giving a total of at least half an hour a day spent waiting for trains.

The obvious solution to this problem is to have trains not go back and forth on one line but instead go from one side of the city to the other. This map shows that there are 14 train lines out of the city with about 5 major lines. The smart thing to do would be to have every major line have one train every 5 minutes during peak hours and to have every train go back out on a different line. Then if you are on one of the major lines and want to travel out on one of the other major lines then every 20 minutes there would have a train that would take you straight there without changing trains!

Currently we don’t even have such frequent trains, during peak hour the trains on most lines run no more often than 5 per hour, the Sydenham line has trains 4 times per hour during peak hours and the trains are crammed full before they get half-way to the city.

If the trains ran more frequently and were routed through the city then commuters who travel through the city would save 20+ minutes per day without going to any effort and 30+ minutes a day if they chose to start their journey at a time to avoid changing trains. This would be a significant incentive for catching the train instead of driving!

For the commuters who travel to work via a single journey then having trains run every 5 minutes at peak times would mean that an average of 2.5 minutes was spent waiting for a train each way (an average of 5 minutes per day) instead of the current situation of 15 minutes per day or more. This would mean triple the number of trains on the Sydenham line which may sound excessive. However the trains are currently so crowded that there could be twice as many trains and all seats would still be full. If there were three times as many trains then I expect that more people would catch the train (surely some people would be convinced to drive to work by the idea of spending 20 minutes with barely room to stand), it’s not inconceivable that there could be three times as many trains and all seats could still be full!

The next issue I have been considering is the time taken for a tram ride to/from the central city areas in peak hours. Peak hour trams stop at every stop because there are always people getting on and off. If a tram could stop less frequently then it could make a slightly higher average speed. One way of achieving this would be for the peak hour trams to stop at every second stop outside the center of the city. On the way in half the trams would accept passengers at each stop (each tram would be designated as either odd or even and labelled as such – the tram stops are already numbered). But if you have twice as many trams then the average wait would be the same while the duration of the trip would be reduced. On the way out of the city the tram driver would announce that after stop 10 (to pick a random number that might work) the tram would only allow passengers to get on or off at even/odd stops. If you knew that your stop was on an even number and the tram was an odd-numbered tram then you would change trams to an even tram. The small delay in changing trams would be made up by a faster trip overall.

Politicians are always talking about ways to alleviate the water shortage caused by climate change and to improve the economy. Having people spend an extra 10 minutes a day working because of saved time on the trains would help the economy. Encouraging people to catch the trains via more frequent and efficient service as well as less overcrowding would help reduce climate change – which is the best way of improving our water supply and the only way of helping the farmers long-term!