Algae as a Biofuel?

I was reading a blog the other day about a Chinese company looking to use algae as a way of absorbing carbon from their coal power stations. The idea is that given that algae needs only sunlight, carbon dioxide and salt water to grow it can be grown in mass quantities using the CO₂ from the coal station. This would in theory produce 'cleaner' coal and a useful by-product as algae can be used as both a fertiliser and as be converted into biofuel.

My problem with this is that are you really saving any carbon from entering the atmosphere?

After digging around for a bit, I came across some useful information in wikipedia. When biomass is burnt as fuel, it releases less carbon than was used in its growth for two reasons,

1. Approximately one third of the carbon absorbed by the plant during its life is sequestered in its roots, which are left in the soil to rot and fertilize nearby plant life, and
2. Combustion of biomass produces 1-10% solid ash (depending on type of plant used), which is extremely high in carbon (this ash is commonly used as fertilizer)

So given that we can convert the biomass into a usable fuel without consuming too much energy (or using energy from other renewable sources) then the net outcome is more power output for only slightly more carbon output. So really this comes down to a question of efficiency... are we better off spending the money researching and developing an algae based carbon absorption plant which then converts the algae into a usable fuel, or are we simply better off using that same money to improve the efficiency of our existing coal power station, or even investing in other renewable technologies?

The graph below gives some idea of the relative carbon intensity (carbon output per unit of energy output) of biofuels against fossil fuels. While it doesn't include algae fuels it does show that it requires less carbon dioxide to extract energy from biofuels in general. This, coupled with the fact that our primary source of food for growing the algae comes from a process that is also generating power, makes for a more efficient process than simply doing either independently and makes a better case than existing biofuels.

It really is hard to say without seeing the numbers. But given that the by-product of the algae may also be used as a fertiliser, and more importantly, that there is a significant amount of R&D in an entirely new field, then I am tempted to say that it is worthwhile. Because even though it may cost more to develop the algae technology, there are other advantages to broadening our approach to energy. For example, algae may be used as a natural source of hydrogen and it is possible to extract ethanol without having to harvest the algae.

In researching all of this I was pretty amazed to realise that biofuels really are becoming an established industry in themselves. I guess this is because they offer a solution that doesn't require major infrastructure changes and they offer a significant solution to the transport industry, which is one of the major (and in some ways hardest to fix) contributors to global CO₂ levels. The things is though, that although we are talking about a more efficient process, the use of biofuels (whether algae or otherwise) still never gets past the key point that we are still putting carbon into the atmosphere at an unsustainable rate. While biofuels may all make us feel a bit better about 'doing our bit', they will never be enough to reduce our carbon output to sustainable levels.

Geothermal Power in Australia

This week saw me attend 'Geothermal Energy - Current Projects and Future Directions', a presentation hosted by the Brisbane chapter of the Institute of Engineers (Society for Sustainability and Environmental Engineering). The presentation included two points of view; one from GeoDynamics, an Australian company that (in conjuction with Origin Energy) has recently completed 'proof of concept' for energy production using 'hot rock' geothermal, the other from a government sponsored research and development centre (in conjuction with UQ), the Queensland Geothermal Energy Centre of Excellence (QGECE).

Geothermal power can be generated using one of two methods. The first, traditional, method generates energy from hydrothermal systems, where fluids circulate through rock fractures where high heat flow is present, typically near active tectonic plate boundaries. Hydrothermal systems are generally used for direct applications and not electricity generation as they may be located in unstable areas and have problems with maintaining sufficient fluid to generate power over time.

The second method, which was discussed in the presentation, involves pumping fluid deep into the ground (3km and below), extracting heat from rocks before retrieving it above ground for use in a heat exchanger. The rocks underground can be very hot, upwards of 200ºC, due to the decay of radioactive material and the kilometers of insulation above them. This provides an excellent source for baseload energy.

Obviously, using the aptly named 'hot rock' (method two) process has complications, not the least of which is having to drill more than 3km underground. But never fear, we have the technology! The oil and gas industry has been developing deep drilling techniques for decades now and it is possible to buy equipment for drilling a long way down. Another problem is finding rocks that are hot enough and over a large enough area. In this case, we are very lucky here in Australia as there are huge regions containing rocks with temperatures greater than 250ºC!

As a side note, while geothermal power is technically 'renewable' it takes many thousands of years for these rocks to heat up once they have been cooled from extracting the heat for energy. Fortunately for us, to reduce the temperature by around 40 degrees (resulting in an approximate 50% loss of efficiency) would take between 25 and 50 years and that would occur over a relatively small area. Given this is a huge resource (albeit out in the middle of nowhere for the most part), investment in geothermal power makes a lot of sense for Australia.

The process to extract energy from hot rocks involves drilling an 'injection' well down into the hot granite approximately 3-5km below the surface. This granite has natural horizontal fractures (due to horizontal compression). These are expanded over a wide area by pumping high pressure fluid into them and forcing the fractures open further. Then a second (and possibly more) 'production' well is drilled to the same depth within the expanded fracture region. Once this is established, fluid is pumped down the injection well, heated by the rock below and retrieved up the production well(s), passed through a heat exchanger and sent back down again. Since the heat of the rocks is so high, the heat exchanger produces enough energy to drive a turbine which in turn generates electricity.

Anyway, back to the presentation. Gerry Grove-White, the Managing Director of Geodynamics, described the process that their business had been through to come to the proof of concept milestone they achieved in early 2009. Their journey was not without difficulty. Gerry described some of the difficulties they had, for example, obtaining equipment as a 'small consumer' in the world of mining, or that there was actually a surprisingly large amount of water under very high pressure (to the order of 70MPa!) down there. This was alongside understanding many of the risks involved in hot rock geothermal power. Things like the ability to create a horizontal fracture, using air condensing rather than Australia's precious water resources, how to manage multiple production wells and whether corrosion (due to radioactive material or otherwise) would be an issue.

Despite all of this, the project has continued with only one major setback - a well blowout in April 2009. This was a fairly major incident although, as Gerry explained, it is not entirely uncommon incident in the oil and gas industry. While the reason for the blowout has not been resolved, there doesn't seem to be any specific concerns regarding the continuation of the project, however there will be some delays in reaching a commercial demostration plant (of the order of 6-12 months).

Gerry finished off with a very interesting note about energy distribution in GeoDynamics' business model. Obviously, having power generated so far from its end consumers creates problem for distribution. One ingenious solution to this was to (particularly in the initial stages) provide the power to consumers willing to use it on or near the site. Examples given for this were data centres and high quality silicon producers, both of which use large amounts of power (which could become very costly when an ETS is introduced) and could be co-located with the plant.

Next up was Professor Hal Gurgenci from the QGECE and it was time to put our theory hats on. It really was quite amazing to hear the difference in the two presentations. One focused on the practicalities of creating a business and the process required to actually create energy (and hence money) from it, while the other was devoted to the theory behind creating a more efficient cycle. Professor Gurgenci described the difference between the standard rankine cycle (commonly used in steam turbines), and a theoretical supercritical cycle using CO₂ as the fluid for heat extraction.

Unfortunately, my memory of 2^nd year thermodynamics failed me and I spent a large section of his presentation trying desperately to follow what was going on! One point I did catch onto though, was the necessity for dry rocks to allow the supercritical cycle to work. Given what Gerry had said regarding the high pressure liquid underground it got me wondering whether there may have been a disconnect between the academic world and the real world as is so often the case. On the plus side however, Professor Gurgenci did present some excellent points on increasing the efficiency of the entire process using concentrated solar power to further heat the fluid once it reaches the surface before going into the heat exchanger.

All in all I thought it was an excellent presentation from both speakers. For someone who knew very little about the entire hot rock geothermal process it was very well explained and was, for the most part, taken from an engineering point of view.

Sources:

Geoscience Australia

GeoDynamics Limited

'Direct use of Geothermal Energy: Opportunities for Australia', GEOCAT #65454, Geoscience Australia

'Electricity Generation from Geothermal Energy in Australia', GEOCAT #65455, Geoscience Australia

'The Power Beneath Our Feet', Tim Flannery, Sydney Morning Herald, April 2005

Greenfest 2009

This weekend saw the second annual Greenfest to be held in Brisbane. I headed down on the last day (Sunday) and was lucky enough to catch some of the great weather we enjoyed this weekend. For those who don't know, Greenfest is a free event with three key elements, purpose, education and production -

Purpose: Accelerate the rate of change in consumer behaviour
Education: Throughout the event from exhibitors to speakers and film
Production: Walking the talk in our own production

This all amounted to a respectable number of stalls, live music and educational talks held in the Brisbane botanical gardens.

As is typical of these kinds of events, there was an interesting cross-section of exhibits. There were the small companies advertising predominantly different solar solutions for consumers, a range of environmentally friendly products and foods, politcal groups and a minor presence from some of the bigger companies focusing in the environmental field in Australia. Aside from the environmental products and foods, which I see as the reason people get dubbed 'greenies' when they mention sustainable engineering, corporate sustainability or the like, most exhibitors seemed very professionally set up and it was great to see just how much interest and room there is in the Australian market for green companies.

However, one of the things I was most impressed with, was the involvement of the Queensland government in Greenfest. I wasn't really aware of just how many programs were being run by the government and the level of thinking (and money) that had gone into them. I must admit that I tend to dismiss state government programs as being generally inefficient and missing the point, but there were some fantastic ideas being pushed at Greenfest, everything from state-wide ethanol initiatives (sugar cane, not corn), to green car guides, to free (for Brisbane city residents) energy monitoring and efficiency audits for your home. I haven't yet looked fully into the details and progress of these programs, but from the surface they look very promising and if nothing else are a very positive step in the right direction. I can only hope that they are not just 'crowd pleasing' programs and that they are the first step in the direction of real green policies and improvements, not only in Queensland but Australia wide.

Another good thing was to see the presence of some serious corporate consulting companies in this space, again I saw this as evidence of a growing industry in Australia for green technology and corporate sustainability.

Unfortunately, I was very disappointed to see a distinct lack of any really big companies/organisations in the green technology sector. For example there was no presence from the Australian Institute of Engineers which have some active societies and projects in Queensland, nor were there any major corporations with green programs. I think if companies are really serious about gaining the most benefit from their green programs then they need to be active in events such as this, otherwise how do people know what's going on? It's the same as the Queensland government's presence, it highlights some of the major programs that they have going and provides people with a chance to understand them a bit better. The only reason I could think of is that Greenfest is simply not big enough yet, nor does it have a big enough following in the corporate world to warrant the presence of these big companies an organisations. Hopefully, as the festival grows over the coming years it can begin to merge these bigger organisations into its lineup.

Having said that, there was a presence from a couple of auto companies, including Mini (BMW), Suzuki, Saab and Telsa all of which had some excellent ideas that came from very different lines of thought. Again though, it was interesting to see that Honda and Toyota, both of which have some obviously great hybrid vehicles weren't present. I particularly liked some of the smart computing technology built into the Saab biofuel demo car, which allows the car to adapt to different ethanol mixes in fuels, anywhere from 0-85% ethanol. This is already an old concept in Europe where the car was introduced in 2006, but this kind of car hasn't reached the Australian market yet, largely due to the lack of high ethanol fuels available.

Anyways, all in all I thought it was a great event, well organised and with a decent turnout. I can only see this event growing in the years to come as more organisations get involved with it and community interest grows.

What's An Emissions Trading Scheme Supposed to Do, and How Can You Tell if it's Working or Not??

You've probably heard all about various emissions trading schemes (ETS) being put in place around the world. Governments and scientists alike hail such schemes as a great way to tackle climate change. But what are they supposed to do and how can you tell if they are working?

Unfortunately, it's very easy to get lost in all of the economic jargon that is bundled up with these trading schemes and if, like me, you don't have a degree in economics then it can all get very confusing. Fortunately, from my point of view, I'm not particularly interested in the way that an ETS actually works. The policy involved and the other economic stuff that makes it all tick is a bit like the inner workings of a wristwatch... as long as the watchmaker knows the details, all I really care about is what it is supposed to do and if it is working or not. But the trick is that you really need to know exactly what something is supposed to do before you can decide whether it is working or not!

So what is an ETS supposed to do? Well in short, it's supposed to put a price on carbon. In doing so, an ETS adds a price representing the environment into the things we buy and use. For example, think of a litre of milk, what prices are involved between it coming out of the cow and ending up in your breakfast cereal? Well, first and foremost, there is the price of breeding the cow, then there are the milking costs, packaging costs, transport costs, storage costs and finally there is a cost of you going down to the supermarket to get it. At no stage does the environment (or anyone representing it) ever stop and say, "Hang on, you've used my land to raise the cow, elements from the earth for milking, packaging, transportation and storage and now you've left me with a heap of byproducts to dispose of, all without ever giving a thought to the impact it may have!".

As the world is coming to realise, the environment spends a lot of time brooding on the amount we take without asking and when it does finally react it doesn't ask us for money. Instead it starts taking away privileges like polar ice caps and consistent weather and plots its revenge through natural disasters. Even worse than that, there is more and more evidence to suggest that the environment is not particularly forgiving in the short term and that the effects of climate change have a certain amount inertia or momentum to them so that even if we start to put things right, we may continue to see the effects for many decades or even centuries afterwards.

But how does this all relate to an ETS? If the environment doesn't ask for money, then what is the point of putting a price on carbon? The answer is simple. While the environment doesn't accept (or respect) concepts like money, humans do. By putting an ETS in place governments are trying to force people to account for the cost to environment in the things they produce and do. Unfortunately, the end consumer tends to bear a large chunk of this cost. While this may seem like a real pain in the short term, it requires slightly longer term thinking to see the real advantages to a strategy like this.

All of this came to mind recently while I was reading (ok I was just skimming through) the International Energy Agency's Energy Technology Perspectives report for 2008 (http://www.iea.org/Textbase/techno/etp/index.asp) the other day and saw this diagram -



The diagram above is referring to some new (clean) technology that is being introduced to the market. Unfortunately, deploying new technology is typically very expensive, but it is assumed that as more units are produced, then unit cost goes down so at some point the cost of the new technology is equivalent to that of the existing (or incumbent) technology. This point is the 'break-even' point. As you can probably work out, the area in the yellow zone is the cost of 'business as usual' for the existing technology. However, because it is new and still requires some acceptance by the market (here they call it 'learning' the technology) there is an overhead of the new, cleaner technology. This is represented by the orange zone.

As is typical of greener technologies, they are cheaper because they are more efficient (and yes I know that is a fairly big generalisation but hear me out), this means that at some stage they will actually reach a break-even point with the existing technology. But imagine if you are a business thinking of investing in this new technology and that the break-even point is 10-15 years in the future. To me, that sounds like a pretty risky alternative... a lot of things can happen in 10-15 years and a lot of money needs to be invested over a long period to make sure it even gets to that point. Well this is where an ETS is really helpful. Because an ETS puts a price on carbon emissions, and if your technology emits less carbon than the existing one, you are at an immediate advantage. Assuming the price of carbon stays relatively constant (and even if it doesn't) then your break even point suddenly becomes a lot closer. In effect you have shifted the goal posts in your favour. This is shown by the BLUE and ACT lines on the diagram, both of which describe a different carbon cost scenario based on IEA modelling.

So at the end of the day, our ETS is making clean technology get to us faster. While it definitely causes some short term pain due to an extra cost on some items, it is worth it for the longer term benefits it brings. For example, imagine if our milk continued to be transported by diesel powered trucks... what happens when oil starts to run out? Diesel prices go up and guess what, so does the price of our milk. But if we pay a little extra for our milk in the short term, more fuel efficient trucks are developed and eventually our milk becomes cheaper.

Just to finish this little post, I'd like to leave you with a thought. Given the current position of the Australian government and its intent to introduce an ETS, is there really any value in giving long term rebates to existing, high carbon emitting industries? In effect removing any competitive advantage that may give newer, cleaner technologies. Given what an ETS is supposed to do, would it then really be working?