What if the energy/climate crisis was solved?

The reality of Peak Oil is pretty much indisputable as far as I'm concerned. If we can't find an equivalent alternative energy source in a big hurry, there's no escaping that the world is going to change dramatically. That's the underlying premise of the Transition movement.

But what if we do come up with an alternative energy source? One which doesn't change the climate, which won't be as destructive to the landscape as coal mining, which doesn't require practically eternal waste management to avoid poisoning the biosphere, which is affordable and practical, and which can scale up fast enough to address the twin crises of Peak Oil and Global Warming?

It's an incredibly tall order. But I'm becoming increasingly hopeful about the possibility of one particular technology, which I've written about before: the thorium-fuelled molten salt fission reactor.

Environmentally-conscious people have an almost instinctive reaction against anything "nuclear", and I understand that. On the basis of long-lived radioactive waste alone I also agree with it, in respect to the current fleet of uranium-fuelled reactors. But the fact is that thorium-based reactors have been designed and even tested which don't suffer from any of the major drawbacks of uranium-based systems.

Features include:
- Abundant, stable, safe raw fuel (100% usable ore vs 0.7% usable from uranium)
- Passive reactor safety (cannot overheat, not pressurised, no complicated mechanical control system)
- Proliferation-resistant (in particular it produces no plutonium)
- Produces very small amounts of relatively short-lived waste (~300 years, certainly manageable)
- Can burn high-level waste from other reactors
- Simple enough to mass-produce in a factory and deliver on a truck
- Electricity probably cheaper than today's coal-based prices

It sounds so good, why wouldn't it have been done before? Well it actually was done before in the 60's and 70's, but the US at the time was more interested in creating plutonium for their weapons program. Hence the molten-salt reactor research program was shut down. Research has now restarted in eight or so countries, including the US, India, France and Japan. Incidentally, Australia has the world's largest reserves of thorium, followed by India.

There is a fairly real prospect of this kind of mass-produced, cheap, safe (enough) reactor technology being available within 15 or 20 years, with known fuel reserves sufficient to power humanity for several millennia.

So what if that came to pass?

Well... it would help. But it wouldn't be sufficient to solve the problems of over-population, destruction of ecosystems, resource depletion and so on. In some ways it could actually make them worse, by providing humanity with the means to continue on with its awful business as usual.

So even if we did solve the energy problem there'd still be plenty of reason to keep working on sustainability in general. That's probably the way I'll be approaching the Transition work - it's absolutely vital if we don't find a new energy source, and it's still hugely worthwhile even if we do.

Solar Tariff Tiff

There's a lot of noise being made at the moment about "feed-in tariffs", or bonus money paid to folks like me for energy that my new solar panels will feed in to the electricity grid. The debate centres around how to measure and price that energy. Here's my take.

There are two main kinds of benefit that large-scale distributed PV electric generation can potentially deliver to the community as a whole: environmental and financial.

The long-term environmental vision, which I'm sure most people would agree is the right idea, is for future society to be powered with cheap, clean, renewable energy instead of being dependent on the burning of coal or the fission of uranium which - even if the technology can be made "clean" - will both eventually run out. An essential feature of this vision is that we must become far more efficient in our use of the energy that is available.

And while it's obvious to most people that harvesting sunlight is sustainable and much cleaner than digging up and burning coal, not everybody is aware that having solar energy generation located nice and close to all our air conditioners is a great way to minimise infrastructure costs associated with peak demand and long-distance power transmission on hot afternoons.

A good feed-in tariff scheme for solar electricity would help to realise both kinds of benefit.

The Queensland Government appears to be following the South Australian lead in proposing a model under which I would only be paid a bonus for producing energy that was not simultaneously consumed within my own home. Just to be clear, that's excess energy which I produce but somebody else gets to use. This is broadly referred to as a "net tariff" scheme.

A number of groups, including the Local Power group through which I've ordered my panels, the Alternative Technology Association, Queensland Conservation, the Queensland Consumers Association and reportedly even BP (who make panels) are expressing disappointment in this and arguing instead for a "gross tariff" scheme whereby I would be paid a premium rate for all the energy produced by my panels regardless of how much energy I consume within my own home, or when. This is reportedly the model implemented in Germany, a world leader in terms of solar electricity generation capacity.

The motivation of the "gross tariff" advocates is fairly simple to understand.

Firstly, most of them genuinely want to see our society move as quickly as possible from fossil-fuel dependency to clean, renewable energy sources - which of course I agree with. Secondly, there's the financial self-interest: panel buyers want faster payback on their "investment" and higher long-term profitability while manufacturers like BP want to sell more panels. And thirdly we have an environmental loopback effect where making panels more financially attractive encourages greater adoption which takes us one step closer to having a clean, renewable energy infrastructure.

However, despite being both an "environmentalist" and a purchaser of solar panels, I don't agree that a gross tariff scheme is an obviously right choice for Queensland as a whole community.

In order to deliver on the environmental potential, the installation of solar panels must succeed in reducing the overall demand for energy from non-renewable sources. And in order to reduce costs associated with the grid infrastructure itelf, that energy must be delivered at times of peak demand. As I see it, the gross tariff schemes being proposed would actually erode both of those benefits from the inside, because it reduces the incentive for the owners of the panels to minimise their own energy consumption. Taken to the extreme, it provides an avenue for wealthy high energy users (and especially those addicted to their air conditioning) to cheaply maintain or even increase their energy consumption. I have actually had conversations with somebody who sees that kind of thing as an opportunity.

(Related post: Does energy efficiency encourage greater consumption?)

In contrast, the net tariff scheme put forward by the state is designed to reward those who find ways to minimise their consumption (delivering the environmental benefit), especially during those hot, sunny times when their panels are producing the most power (delivering the peak load infrastructure cost benefit).

Australian taxpayers are already contributing $8,000 towards my panels through a federal scheme to stimulate growth in the PV industry. Why should my fellow Queenslanders pay me even more in a subsidy which I could squander by simply using more energy and defeating the purpose of all that investment in the first place?

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Speaking of the bigger picture, I believe that the actual core problem here is that current retail energy prices are much, much lower than the true cost of the energy. Government subsidies to the coal industry, myopic belief in unlimited growth and a very bad habit of completely ignoring "externalities" have made it so. Gross tariff proposals make a certain amount of sense in that they come closer to recognising the complete value of the energy, but the proper objectives of such a scheme would be continually undermined by the disincentive to reduce consumption.

Maybe as a kind of middle-ground policy it would make sense for panel owners to be paid a modest flat rate for their gross production on the proviso that they sourced at least the same quantity of energy (or 100% of their consumption, whichever is lower) from GreenPower-accredited providers. That would help to direct funding into renewable energy projects. Mind you, panel owners could achieve almost exactly the same thing by simply not selling their RECs at the time of installation. (See my earlier post on that topic.)

Perhaps surprisingly, I'm leaning towards opposing "time-of-day" metering for retail electricity consumption at this point. The idea behind it is to charge consumers more for energy consumed during peak periods. Sounds sensible enough, but apart from smoothing the load on the distribution grid it actually favours the coal generators and erodes the benefit of having a substantial PV capacity. However if it could be shown that time-of-day metering reduced overall energy consumption and especially consumption of fossil fuels then it might be worth doing.

But the "elephant in the room" (to borrow a phrase I once heard used by Andrew McNamara) which apparently nobody is talking about is that over the lifetime of any new solar panel installation the retail price of energy is likely to go up dramatically. You can thank climate change, carbon trading, peak oil and population growth for that. Even without any kind of tariffs, that rise should significantly shorten the effective payback time for a PV installation through avoided energy costs in the future.

More on Howard's "Clean Energy Target"

Since reading this morning's announcement and posting my initial response, I've come across more coverage from the ABC including an interview with Federal Minister for the Environment, Malcolm Turnbull. The transcript is here.

Apart from the mandatory political bluster and spin, there was this most amazing statement from the minister:

"Our approach to climate change... is pragmatic and practical. We are determined to meet this [target], we are determined to get to the point in the course of this century, where the whole world has a zero emission electricity sector, and we will aim to achieve that in Australia, but we've got to get there and do it practically."

I was only this morning wondering to myself when we'd see a political party come out with some kind of long-term vision for energy supply, and in particular whether it was too much to ask for a party to look ahead to a 100% renewable, sustainable energy infrastructure. Out of the blue (no political pun intended) Mr Turnbull drops half of my dream into a national radio interview.

The whole world, with a zero emission electricity sector, this century. Credit where it's due: that's a great goal.

However... and you knew that had to be coming... zero emissions technology does not necessarily mean sustainable or even particularly desirable technology. Wind power has no waste products. Coal plants have megatonnes of CO2, fly ash and contaminated water, plus an ongoing dependence on oil for coal mining and transportation. Uranium-based nuclear is arguably worse. And in time even coal and uranium supplies will dwindle, leaving the world dependent on a greater energy supply than it can sustain.

(Rhetorically:) Minister, what would it take for you to at least aspire to a truly sustainable clean energy future? If not this century, then next? How much could we achieve even by 2050 if we truly put our hearts into it?

I begrudgingly concede that this is a step in the right direction, a slight improvement over what was. But I have to agree with John Connor of the Climate Institute who pointed out that Spain has a target of 30% renewable energy by 2020, prompting the question of why in sun-drenched Australia we couldn't aim to match or better that.

Still a case of "target, schmarget" as far as I'm concerned. Somebody bring me some real policy.

Target, my arse!

I hope that subject line got your attention. Because that's exactly the strategy employed by our Prime Minister with his weekend announcement of a "National Clean Energy Target". Hopefully I've got something more useful to say than he does.

The more astute reader may have already picked up on my subtle hints and started to suspect that I'm not particularly impressed with Mr Howard's efforts in the area of clean energy. But for the sake of not being an arse myself I'll make the majority of this post as objective and even-handed as I can, starting... now.

There are three major aspects to the announcement: the what, the how and the when.

What: 30,000 gigawatt hours of energy per year. It sure sounds like a lot (it's meant to) but it's a funny way of putting things. Since one year has around 8,760 hours in it we can convert it to a measure representing the average instantaneous rate of power generation. Dividing 30,000 by 8,760 gives a smidge over 3.4. That's 3.4 gigawatts. To put that into perspective, Tarong power station in South-East Queensland has a generating capacity of 1.4 gigawatts, so we're talking about just under two and a half Tarongs worth of energy. I've loaned my copy of Mark Diesendorf's book to a friend so I can't look up what fraction of Australia's total present energy generation that is but my initial estimate would be "not much". To be fair, increasing our total renewable energy capacity to this level would be a significant step forward, but see the next paragraph.

How: This is not a "renewable" energy target or even a "sustainable" energy target. This is an allegedly "clean" energy target which refers to "technologies that emit less than 200 kilograms of greenhouse gases per megawatt of electricity generated", explicitly including coal-fired systems with carbon capture and presumably including uranium-based nuclear plants. There's a serious omission in that definition, which is the amount of time over which those emissions will be measured. Multiplying 200kg/MW by 3.4GW gives 680 tonnes. But is that 680 tonnes per year? That would be quite impressive actually, but it could well mean 680 tonnes per HOUR. Regardless, it appears to be a business-as-usual approach from a government which has pledged its support for the coal and nuclear industries, declared its faith in the gospel of carbon capture and storage and demonstrated its disinterest truly clean, renewable, sustainable energy sources.

It must also be pointed out that this scheme is intended to replace all the existing state-based schemes and coalesce them into a national one. There could be some real advantages from an administrative and economic perspective in doing this. But whereas the existing schemes are largely being implemented using true renewables this new arrangement seeks to bring coal and possibly uranium-based nuclear energy under the same umbrella.

When: Mr Howard's announcement sets the year 2020 as the goal for implementing this scheme. That much at least is clear and unambiguous. But if 3.4GW is only a small fraction of today's consumption, it'll likely be a much smaller fraction in twelve years time unless dramatic action on energy-efficiency is taken between now and then.

In the end this policy has the appearance of a misleading pre-election publicity grab designed to give the marginally-concerned majority the impression that the Liberals are being proactive about addressing climate change and sustainability, when all they actually intend to do is sweep the carbon under the rug and rush to build uranium-based nuclear plants as soon as they possibly can.

Regarding baseload power

Just following up on my last post where I briefly mentioned that the reason we can get such cheap power on off-peak rates is that coal-fired power stations can't be shut down overnight and the energy they produce has to go somewhere.

Found an interesting article today (via EcoGeek) from which I take the following quotes:

"Baseload is what those older technologies provided, not what we need... We need something that follows the natural load."

In other words, the grid is currently constructed to accommodate capital-intensive fossil fuel plants that need to run 24/7 to be most efficient and economical. The natural load, on the other hand, is the demand for electricity created by people's and the economy's daily rhythm. That demand naturally peaks when people are up and about and falls at night when they're asleep. Renewable energy sources, Mills argues, more closely mirror human behavior. Solar electricity production soars when demand does during the day. At night, stored solar energy and other renewable sources like wind, which tends to blow strongest in the evening, can more closely match lower demand as people and machines wind down.

Those of us who wish to support the expansion of the renewable energy industry need to counter the argument that renewables cannot supply sufficient baseload power. Perhaps we should be pointing out that the demand for such high power consumption overnight has been artificially generated to suit the coal-fired power stations.

But I'll also take that as justification for my decision to invest in a solar water heater even though it doesn't appear to make economic sense under current conditions. By reducing our night-time electricity consumption I'm ever so slightly changing the demand curve and eroding the argument that we need technology which can provide such large amounts of energy 24 hours a day.

Money and power

This past week has had a fairly clear theme for me: the price of energy. There's the record-breaking crude oil prices, a discussion at our BNCWAG meeting about the confusing options for buying renewable electricity and then of course the replacement of our hot water system with a solar one.

Lets leave the oil issue alone for the moment (partly because the record prices are being kicked along by a weak US dollar which reduces the significance of the raw numbers). Just now I'm more interested in the electricity market.

Here in Queensland the energy market is regulated. There are fixed tariffs for the supply of electricity to various types of customers for various purposes. Most homes have two circuits: one which supplies electricity for general domestic purposes 24 hours a day for roughly 15c per kWh, and another which typically is connected to a water heater but only works during off-peak hours and is billed at a much lower rate (as low as about 6.5c per kWh).

These prices are the new ones, following an increase at the start of July which was largely attributed to the rising cost of producing electricity with cooling water being in short supply due to the drought. Ironically the drought conditions have led to a significant reduction in shower times and a corresponding reduction in the amount of water heating required. My most recent figures have us averaging 7.3kWh per day this winter at a cost of around 47c.

Now here's the bit which is bugging me. If my shiny new solar hot water system was so good that it never needed any electrical boosting (it's not), and assuming that we required that same amount of heating all year round (we don't), it would take just shy of 30 years for us to recoup the cost of the new unit from the savings on our electricity bills.

I can imagine my wife's raised eyebrow and my father's shaking head about now. But even having run these numbers I would still make the same decision again. It's only bugging me because it makes it harder to convince other people that it's a decision they'd want to make too. There are three reasons I want to point out here.

1. This is mostly about saving energy, not money

The pursuit of short-term economic advantage is what led to our current dirty coal infrastructure and is what maintains the hegemony of the coal industry in Australia's energy industry.

The reason that electricity is available at less than half price overnight is that the massive steam turbines in the coal-fired power plants cannot be switched on and off in a daily cycle. The operators of these plants need to smooth out the demand curve over the course of the day and these skewed pricing arrangements help them achieve that by encouraging additional energy consumption during the night.

It works too: this past quarter my water heater used more energy than everything else in the rest of the house combined! Though it will reduce our bill by less than 30% and at these prices will never pay for itself, installing a solar hot water system is going to approximately halve our total electricity consumption.

2. Electricity prices are likely to rise sharply - even for dirty coal.

There are a number of pressures on the electricity market which I suspect will cause prices to rise sharply over the next couple of decades. If you forgot about sustainability concerns completely you'd still have decreasing availability of cooling water, increasing global demand for coal, increasing local demand for electricity and the need for infrastructure work on generation and transmission.

Now I do hope that the sustainability and environmental agenda is going to have a powerful influence on future policy and development. This would lead to greater reliance on wind and other renewables which have a lower overall capacity, generally higher cost (than the present price of coal where many costs are subsidised or simply not accounted for) and a different delivery profile (solar, for example, is obviously linked to daily cycles).

All in all I expect the price of a unit of energy for the end user like you and me is going nowhere but up. Hopefully through a range of efficiency measures we can keep our overall costs from rising. My Solahart might turn out to be an economic winner in the future.

3. It's in keeping with the philosophy of sustainable design

I keep thinking back to McDonough's work on architecture and building design and his philosophy of making the best use of the available natural resources. Without the solar water heater up there the sunlight's energy would be wasted. My vision for the future is nowhere near as vivid as McDonough's but I'm quite certain that I'd expect to see solar heating in a place like Brisbane.

Understanding Energy - Part 2 of 2

Yesterday's bottom line was this: all the Earth's energy comes from the Sun, it provides life with the ability to grow and to modify the materials of the Earth, and the majority of it eventually heads back out into space as waste heat.

The ancient civilisations of places like Egypt and South America seemed to understand this much better than we do today. Modern man knows clever words like "photosynthesis" but has lost the deep understanding that the Sun is ultimately what puts leaves on the trees and life in our bones.

My best guess at why this is comes down to the discovery of fire, and of "non-living" things which could be burned. Of course I'm referring to coal, oil and natural gas.

Fire is a chemical reaction in which energy that was previously holding atoms together to form molecules is released as heat. Because there's a high concentration of heat energy in one place it's possible for us to channel some of it into causing desirable changes (such as pushing a piston in an engine, melting metal in a furnace or cooking food on a BBQ) before it dissipates and becomes "lost".

For many thousands of years the primary source of chemical energy which humans could harness by setting it alight was wood. Trees spend years soaking up solar energy and converting it to chemical energy that holds together the atoms which form the molecules that comprise its living tissues. At this level the connection between the Sun and the energy available to us in a wood fire is still somewhat intuitive. It's fairly obvious that the trees have to grow before they can be burned.

But coal, oil and gas don't have that same obvious relationship to the Sun. Instead of waiting for a tree to grow you can just dig them up and burn them. And what's more, the amount of chemical energy they contain is far greater than in their equivalent weight of wood. The industrial revolution was unleashed upon the world when people started to figure out more sophisticated ways of using that stored chemical energy to cause changes in materials and motion. That revolution never stopped - we are still living it at full throttle today.

There's just one little problem. Do you remember the two rules of the energy game from yesterday's post?

1. Energy cannot be created or destroyed.
2. Whenever energy is used, some of it gets "lost" and can't be used again.

All that energy in oil didn't just magically appear. Scientists are pretty darn sure that coal and oil and natural gas were formed from the accumulation, over hundreds of millions of years, of solar energy converted by plants into chemical energy and then trapped underground in landslides, floods or similar events. That's why they're called "fossil fuels".

It's like the Earth has an internal rechargeable battery. It's capable of storing an unimaginable amount of energy, and it's in a form which is wonderfully convenient for us to use. It took hundreds of millions of years to charge it up, but in the span of a couple of hundred years we've managed to run the battery down to about 50% charge remaining and at this rate it'll be fully exhausted by about the end of this century.

Let me say that again. We've consumed hundreds of millions of years worth of stored solar energy in just a few centuries, and now we're starting to run out.

The discussion about how much fossil fuel energy remains to be dug up and burned is a complicated one and is made worse by the unfortunate side-effect that we call climate change. I'm going to side-step the whole question of exactly when fossil fuels will cease to be able to meet our energy needs for transport and electricity production - but it will inevitably happen. In many parts of the world energy supply is already struggling to keep pace with demand.

But what else is there?

Governments and corporations the world over are turning to "biofuels" to try and compensate for falling oil production. But the math just doesn't add up: the rate of conversion from sunlight to chemical energy is far too slow to allow it to meet the current demand for oil. Besides which, studies seem to show that in many cases you use about as much oil producing the crop (for powering farm machinery etc) as you get back from the crop in the final product, making the whole enterprise a waste of oil and food at this point in time. Technological advances may make the process more efficient in the future, though, so continued research is worthwhile.

Solar photovoltaic technology - which uses tricks of physics to convert sunlight falling on a substance directly into electricity - has a similar problem. The technology keeps getting better but there's a limited amount of the raw materials needed to make the panels and producing them consumes significant amounts of energy. We probably can't produce enough of them and they don't give back enough energy to make them a silver bullet solution to our electricity dependency, but again more research is needed.

Heating water with solar collectors is a no-brainer and I applaud moves from the Queensland government to phase out the old electric-powered type. Wish it would happen sooner.

Using wind to generate electricty (converting kinetic energy from the moving air into electrical energy in the turbine) is also a pretty smart idea. The wind moves because the Sun heats the air, so tapping into that energy flow is sustainable in the true sense of the word. There are some concerns about the amount of energy used in construction vs the amount of energy the turbine can harness over its lifetime, but those issues can probably be solved through engineering.

Hydro-electric systems are also driven by the Sun. It's the Sun which heats the water and causes it to evaporate. It's the Sun which drives the wind that carries the vapour up over the higher land, imbuing it with gravitational potential energy. As the water flows down again towards sea level we can extract some of that energy to turn a turbine and convert it to electricity.

Wave and/or tidal energy. Waves are caused by the wind, which in turn is powered by the Sun, and there's a colossal amount of kinetic energy in the movement of the water. Harnessing that's a great idea. The tides are due to the gravitational pull of the Moon on the water. Taking energy from that system will actually cause the Moon to orbit more slowly and crash into Earth... but that's going to happen eventually anyway and it's unlikely we'll make any significant impact. (No pun intended.)

Geothermal (hot rocks). Not, strictly speaking, a renewable resource but definitely a clean one. Worth looking at where the geology is appropriate.

Nuclear. Ah, had to get to this eventually. Ultimately, nuclear energy is a form of stored energy that was locked into atoms by long-dead stars. It's completely natural but - like molten lava or the Sydney funnelweb spider - not something you want to get too close to. It's interesting to note that some of the geothermal heat which people want to harness was actually released during the radioactive decay of unstable nuclei. There is a lot of nuclear energy available to us here on Earth but like fossil fuels there are undesirable side-effects and it's not a renewable resource.

And that, pretty much, is it. We need to stop using fossil fuels now due to global warming but we will simply run out of oil soon anyway. Nuclear technology will continue to play a role in the global energy mix for a very long time, and it's possible that new developments could greatly reduce the risks associated with radioactive waste and other concerns. The rest of them are all important because none of them can supply so much energy in such a convenient form as fossil fuels have done for the past couple of centuries.

There's a lot of work needed to secure energy supplies and maintain a habitable planet, even just for the rest of this century. I've started doing my bit and you can too.

Thanks so much for reading this far. Questions, comments, corrections all are welcome.

Water

Australia is suffering a devastating drought. We have no idea whether it's a temporary abnormality or a new weather pattern caused by global warming which is going to stick with us for the long term.

Brisbane's water storages have dropped to under 20% capacity. Hundreds of millions of dollars are being spent on water infrastructure in this region alone, including new dams, pipelines, desalination and reclamation (recycling). It's appalling that our response to a drought which may be caused by global warming is a massive project which first burns oil to power the construction machinery and then coal to power the desal plant and all the pumps. It may in fact be our only option to survive the present conditions but still...

The nation's major food producing region (the Murray-Darling basin) has just been informed that in the absence of significant rain in the next couple of months there will be no water available for irrigation later in the year. If this eventuates, future recovery would take years as long-established trees and vines are likely to die.

All these water woes aren't restricted to humans though. Environmentalists have been telling us for years that our abuse of water destroys ecosystems upon which we all depend. Now the pressure on the environment is coming from both sides: what little rain there is is being consumed by us, with basically nothing left.

No Silver Bullets (re Peak Oil)

My previous post was about the tension between the growing demand for oil and predictions of declining availability, and the relationship of oil consumption to global warming.

I expect that many people reading that post would quickly reassure themselves by thinking about one or more of the following:
- biofuels (especially ethanol for use in existing cars)
- electric, hybrid or hydrogen-powered vehicles
- coal liquefaction (literally converting coal into a fluid form similar to oil)

Here's why none of those make me worry much less, if at all.

1. Biofuels

The basic idea is neat: instead of giving carbon a one-way trip from oil to the atmosphere, lets grow plants to take CO2 out of the air then convert it to fuel which when burned puts the carbon back where it came from. The overall amount of CO2 in the air stays constant and we don't need oil.

But already we've hit a fatal flaw with biofuels: in fact the production of ethanol from, say, corn requires massive inputs of oil in the form of fertilisers, pesticides and fuel for agricultural machinery and transport. It also requires significant electrical input which - especially in Australia - basically means burning coal. So we're still consuming oil and adding CO2 to the atmosphere even before the ethanol gets into our petrol tanks.

Fatal flaw #2 is so obvious I'm stunned we are even bothering to attempt growing fuel. Our cars and trucks and planes and ships consume enormous amounts of fuel. Even if we dedicated all the productive land on the planet to growing fuel crops we would only manage to produce a fraction of the fuel we need to keep everything running at the current pace - let alone meet the exponential demand predicted for the future.

There is some research being done into growing algae in tanks or ponds as an alternative to land-based fuel crops. This may lead to a significant, sustainable biofuel industry and I'd be encouraged by that. But from what I've read it's still not likely to ever be enough to match our current appetite for oil.

2. High tech cars

It's true. We can make cars which don't need to burn oil.

Some people are keen on cars similar to the ones we have today but which burn hydrogen gas (H2) instead. There's no "C" in hydrogen, so when you burn it you just get H2O. Water vapour. But hydrogen gas is highly explosive (can you say "Hindenburg"?) and it's very difficult to handle. Oh yeah, and water vapour is a much more powerful greenhouse gas than is carbon dioxide.

So there's a lot of attention on using hydrogen in fuel cells - basically little modules of hardware that generate electricity through chemical reactions and which you'd either swap in and out of your car like rechargable batteries in a camcorder, or top up with additional hydrogen. Fuel cells are real enough (they're used in the Space Shuttle, for example) but the technology needs a fair bit of development before it's suitable for use in everyday transportation.

Sounds good, huh? Uh-oh, here it comes.

Hydrogen's fatal flaw when it comes to the global warming / peak oil dilemma is that it generally isn't a source of energy but a carrier of energy. Hydrogen can't be mined*, it has to be produced. The simplest way to produce it is to push an electric current into water so that you give the hydrogen atoms the energy they need to escape their bonds to the oxygen atoms. That's how it acquires the energy which we want to use later on when we burn it in an engine.

Fuel cells and electric vehicles get lassoed with the same rope now. All these vehicles depend on large inputs of electrical energy. Hopefully you recall that our electrical consumption is already a major concern because of the CO2 we emit when we generate it. Unless we come up with a revolutionary large-scale way to produce electricity, these cars would simply drive us from the peak oil frying pan into the global warming fire.

3. Coal liquefaction

I only learned about this one recently, but it's old technology. During one of the Great Wars the British were astonished that their attacks on the German sources of oil didn't bring the Nazi machine to a halt. The Germans had prepared by switching to production of liquid hydrocarbons from coal.

The world does have heaps of coal (though calculations for "Peak Coal" are already being debated) and I get the impression that it's relatively simple and efficient to convert it to a liquid. On the positive side, this may help alleviate the shortage of raw material for plastics and fertilizers etc. But of course burning the stuff in cars is just as bad as burning it in power stations. As a greenhouse-friendly replacement for oil, coal is also fatally flawed.

Three bullets: shiny-looking, but definitely not silver.



* I am simplying things a fair bit with regards to hydrogen as an energy carrier but it's generally true that getting usable H2 on a very large scale would require massive energy input and that would predominantly come from coal at this point in time.