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Tag Archives: biofuels

Biomass and renewable gas

By Dave Elliott

Not everyone backs biomass, given the emission/biodiversity/land-use issues, but  biomass does offer a range of flexible green fuel options, biogas especially.  The World Bioenergy Association (WBA) says bioenergy already contributes over 14% to the global energy mix, and its use is bound to expand.  So what are the options? (more…)

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Bio-energy in the UK

By Dave Elliott

There is a lot going on in the bioenergy field in the UK, with the government keen on biomass conversion of large old coal fired plants like the 4GW Drax plant in Yorkshire. That’s based on importing wood pellets from North America, something most greens are opposed too (see my last post), especially if it uses whole trees, as some allege:


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Energy return on energy invested

by Dave Elliott

There is inevitably some energy ‘embedded’ in energy generation systems, and it is useful to compare the energy needed to build and run plants relative to the useful energy out, but estimating ‘Energy Returns of Energy Invested’ (EROEIs) can be tricky. The ratios can range up to 200:1 or more, and down to single figures- very worryingly since then it is hardly worth running the plant.


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Bioenergy is good

by Dave Elliott

In a new book ‘The Sleeping Giant Awakens-Bioenergy in the UK’ (Alba press), Stewart Boyle, a former green activist turned energy consultant and woodland owner, who has worked in the bioenergy sector for 12 years, sets out a strong critique of the current status of bioenergy in the UK. Controversially, he takes issue with the conclusions of some green pressure groups who have of late opposed reliance on biomass. ‘Having reviewed the science and the arguments, I feel that some of the NGOs have lost the plot on bio-energy and are using really bad science without thinking through their long term energy strategy.’  He claims the UK could get at least 10% and maybe over 20% of its energy frombioenergy in heat, transport, power and bio-chemicals.


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Biomass for energy debated

By Dave Elliott

The use of biomass to produce electricity need not cause significant land-use tensions and Government should look to support the development of this type of power generation with Carbon Capture and Storage (CCS), according to a new policy statement by the Institution of Mechanical Engineers.


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Hydro – and beyond 2

By Dave Elliott

In my previous post I looked at the role of hydro power, which dominates in many developing countries and regions, supplying nearly 100% of electricity in Albania, Angola, Bhutan, Burundi, Costa Rica, D R Congo, Lesotho, Mozambique, Nepal, Paraguay, Tajikistan and Zambia, as well 60–90% in 30 other developing countries. See

However, as I indicated, there are concerns that, given a range of environmental, social and political issues, large hydro may not be the best option for the future, whereas smaller-scale projects, including micro hydro, wind and PV solar, might be better suited to development goals and local needs. See–and-beyond.html.

I focused on Africa, but the dominance of hydro is even greater in South America. Brazil, the leading economy in the region, already gets 87% of its electricity from renewables, mostly hydro. However, it is trying to diversify, with wind and solar. So are some of the less-developed countries in the region. Nearly 100% of Paraguay’s electricity comes from hydro, but it is trying to expand other renewables, as are Patagonia, Bolivia and Ecuador, with PV especially favoured. Colombia, which currently gets 70% of its electricity from hydro, is investing in wind power: it has an estimated theoretical wind-power potential of 21 GW.


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Biofuel policies navigate between Scylla and Charybdis

By Felix Creutzig

Governments seek to mitigate climate change and make their countries energy independent. Biofuels seemed to achieve both: sequestering the carbon they emit, biofuels were considered carbon neutral; they also rely on intra-regional resources, notable land, and reduce oil imports.

But study after study points to unforeseen dangers. The current aggressive deployment of biofuels compromise food security; and perversely, biofuel production contributes to climate change by releasing carbon formerly stored in soil and forests (indirect land use change, ILUC).


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Biomass limits (Part 1)

An 18-month inquiry by the independent Nuffield Council on Bioethics (NCB) has found that rapid expansion of biofuels production in the developing world has led to problems such as deforestation and displacement of indigenous people. The need to meet rising biofuel targets has also led to exploitation of workers, loss of wildlife and higher food prices. Biofuels also contribute to poor harvests, commodity speculation and high oil prices which raise the cost of fertilisers and transport. However, it says, there is a clear need to replace liquid fossil fuels to limit climate change and if new biofuel technology can meet ethical conditions, there is a duty to develop it.

NCB say an international certification scheme, like the Fairtrade scheme for food, was needed- to guarantee that the production of biofuels met the five ethical conditions identified by the NCB: observing human rights, environmentally sustainable, reduced carbon emissions, fairly traded and equitably distributed cost and benefits.

In a new report, the Food and Agriculture Organization of the United Nations (FAO) similarly claimed that bioenergy could be part of the solution to climate-smart agricultural development, but only if their production was properly managed. Large-scale liquid biofuel development, in particular, may, they say, hinder the food security of smallholders and poor rural communities, and enhance climate change through greenhouse gas (GHG) emissions caused by direct and indirect land use change. It’s therefore crucial they say to develop bioenergy operations in ways that mitigate risks and harness benefits. Safely integrating both food and energy production addresses these issues by simultaneously reducing the risk of food insecurity and GHG emissions, and Integrated Food-Energy Systems (IFES) can, they claim, achieve these goals on both small- and large-scales.

This may sound like wishful thinking, but FAO offers concrete options for how smallholder farmers and rural communities, as well as private businesses, could benefit from these developments and attempts to give a holistic picture of the different types of energy that can be produced from agricultural operations, and how they can be aligned with current food production schemes. [

The International Energy Agency similarly seems convinced that, given proper controls, biofuels can play a major role. In its new Roadmap, it says that they could supply 27% of global transport fuel by 2050, on a sustainable basis. The IEA says that ‘while vehicle efficiency will be the most important and most cost-efficient way to reduce transport emissions, biofuels will still be needed to provide low-carbon fuel alternatives for planes, marine vessels and other heavy transport modes’. With optimised policies in place, the report predicts that biofuel production could grow from 55 million tonnes of oil equivalent (Mtoe) today to 750 Mtoe in 2050.

To protect land for food production, the IEA suggests using 1 billion tonnes of residues/wastes, and 3 billion tonnes high-yielding non-food energy crops, the so-called second-generation technologies, such as cellulosic ethanol. Even so, production would have to be supplemented with around 100m hectares of land – around 2% of total agricultural land, a three-fold increase compared with today. And the report admits that the 27% target is only attainable if lignocellulosic technologies are produced at an industrial scale within 10 years, and would require government support and research and development investment of more than $13 trillion over the next four decades and an international support programme. But it was claimed that ‘biofuels would increase the total costs of transport fuels only by around one per cent over the next 40 years, and could lead to cost reductions over the same period.’

The report warns that the use of fossil energy during cultivation, transport and conversion of biomass to biofuel will have to be reduced, while direct or indirect land-use changes, such as converting forests to grow biofuel feedstocks which release large amounts CO2, must be avoided. The IEA says that it is important to impose sustainability standards for biofuels to prevent harmful impacts on land, food production and human rights. It suggests a land use management strategy be imposed along with a reducing in tariffs to encourage trade and production of biofuels.

Are these proposals realistic? It ought to be possible, at least in theory, given the right regulatory framework, to avoid food-energy conflicts, but even with the best technology, there’s still a risk that commercial pressures, locally and globally, for high added value vehicle fuel production will overwhelm any efforts at balance and integration- energy is the ultimate cash crop. For example, not all of it is for vehicles, but only 6% of the current global supply of palm oil meets sustainability standards: see:

If we move away from high added-value products like biofuels for transport, the situation gets a little easier. Biomass can also be used for heat and power. Indeed many argue this make more sense- since the final energy yields/acre using solid woody biomass are generally higher than for liquid biofuel production.

The Potsdam Institute for Climate Impact Research (PIK) has looked at the overall global potential for biomass and concluded that it could meet up to 20% of the world’s energy demand in 2050, half of it from biomass plantations. But that would involve a substantial expansion of land use, by up to 30%, depending on the scenario, and irrigation water demand could double.

In the PIK study, fields and pastures for food production were excluded, as were areas of untouched wilderness or high biodiversity, as well as those forests or peatlands, which store large amounts of CO2. But with second generation (non food) energy crops, the bioenergy potential ranged from 25 to 175 exajoule by year: the lower outcomes are for strong land use restrictions and without irrigation, the higher outcomes assume few land use restrictions and strong irrigation.

A middle scenario would result in about 100 exajoule, while the world’s energy consumption is estimated to double from today’s 500 to 1000 exajoule by 2050. It’s claimed that roughly the same amount of energy production, in addition to biomass plantations, could result from agricultural residues. Hence the 20% headline figure, with increased use of residues instead of cultivating dedicated energy crops seen as crucial for a sustainable future.

Beringer, T., Lucht, W., Schaphoff, S.: Bioenergy production potential of global biomass plantations under environmental & agricultural constraints. GCB Bioenergy, 2011 [doi:10.1111/j.1757-1707.2010.01088.x]

A new study funded by the UK Energy Research Centre (UKERC) came to similar conclusions, at least on the benefits of using non-dedicated land, in the UK context. It looked at the potential of planting short rotation coppice (poplar and willow) in England, taking into account social, economic and environmental constraints and concluded that planting short rotation coppice energy crops on England’s unused agricultural land could produce enough biomass to meet renewable energy targets without disrupting food production or the environment.

The UKERC study, published in Biofuels, says that new technology will enable bio-fuels to be made from lignocellulosic crops (e.g. short rotation coppice willow and poplar), which, unlike current cellulosic crops (typically derived from food crops such as wheat and maize) can grow on poor-quality agricultural land. While the results suggest that over 39% of land in England cannot be planted with SRC due to agronomic or legislative restrictions, marginal land (ALC grades 4 and 5) is realistically available to produce 7.5 m tons of biomass. This would be enough to generate approx 4% off current UK electricity demand and approx 1% of energy demand. The SW & NW were seen as having the potential to produce over one third of this, owing to their large areas of poor grade land.

Not everyone will agree that, even with new types of crop, biomass can be much of an options, but in Biomass limits 2, next week, I’ll be looking at some radical technical fixes that might improve the situation for biofuels and/or biomass use.

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Carbon accounting policies for biofuels

In a recent post. Not all biofuels, however, have the same carbon footprint. How can biofuels for transport and their life-cycle greenhouse gas emissions then be effectively regulated?
As pointed out in the corresponding paper are insufficient for not accounting for a series of general equilibrium effects. The European Commission, in fact, is currently reviewing its stance, and may review the FQD in this summer. But what kind of measure can improve the biofuel conundrum?
The twin paper by Flachsland et al. studies a potential role of emission trading also for the transport sector. Now, this is an effective measure in terms of bringing a level-playing field across all fuels. In fact, if a cap is global in scope, and covers all relevant sectors, we could sleep quietly: wherever emissions appear they will be accounted for, and it is not relevant whether they are induced by biofuels or not. It matters only that they get a price tag, and that people try to reduce emissions.
However, a global cap is not in sight, and an inclusion of agricultural emissions also seems utopian currently. Hence, we are still stuck with the GHG accounting problem for biofuels (and potentially relevant general equilibrium effects for other fuels such as electricity) when transport is included in the European Emission Trading Scheme.
One possibility is to treat biofuels by default as having at least gasoline-equivalent emissions (see DeCicco, 2009 and processing emissions, gaining credits if certified. This would reverse the burden of proof. Properly implemented, it can be seen as an implemented precautionary principle – better safe the forests and its carbon stock then being sorry big time.

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The EROI of algae biofuels

In an earlier blog post (“The Algebra of Algae…to Biodiesel”) I discussed if the US was to reduce its CO2 emissions to 17% of those in 2005 (mimicking the ‘popular’ climate legislation from two years ago in 2009), then the US could produce 50 billion gallons of biodiesel from an algae feedstock. Aside from later being told that titling the blog “Algaebra” would have been much better (what I agreed with at the time), I have now discovered that the web is littered with discussions of brassieres made of algae. I’m glad I used my previous title!

But I digress, the caveat for my previous blog on algae biodiesel was is that to meet the CO2 emissions limits there could be no other source of CO2 emissions other than the power plants that would be capturing CO2 and piping that CO2 to the algae farms. There is also the possibility of using CO2 directly from the atmosphere to grow algae, but most algae-facility designs assume a source of concentrated CO2 to grow the algae feedstock. Clearly we need to understand the limitations of using ambient air, and the inherent CO2 in the air, versus supplemental CO2 from anthropogenic sources.

Over the last year a student (Colin Beal) at the University of Texas, Austin, has been characterizing the experimental set-up at the Center for Electromechanics for testing an algae to bio-oil process. The process stops short of converting the bio-oil into biodiesel, and he presented the results at a recent conference: Beal, Colin M., Hebner, Robert E., Webber, Michael E., Ruoff, Rodney S., and Seibert, A. Frank. THE ENERGY RETURN ON INVESTMENT FOR ALGAL BIOCRUDE: RESULTS FOR A RESEARCH PRODUCTION FACILITY, Proceedings of the ASME 2010 International Mechanical Engineering Congress & Exposition IMECE2010 November 12–18, 2010, Vancouver, British Columbia, Canada, IMECE2010-38244.

Colin counted the direct (electricity primarily) and indirect energy (nutrients, water, CO2, etc) inputs into the process along with the energy content of two outputs: the biomass of the algae itself and the bio-oil extracted from the algae. He did not count the energy embodied in any capital infrastructure. What he found for this experimental, and very batch process was that the EROI of the experimental process was approximately 0.001.

This experimental EROI value for energy from algae must be kept in perspective of the stage of development of the entire technology and process of inventing new energy sources and pathways. It is important that we understand how to interpret findings “from the lab” into real-world or industrial-scale processes. To anticipate the future EROI of an algae to biofuel process, Colin performed two extra analyses to anticipate what might be possible if anticipated advances in technology and processing occur: a Reduced Case and Literature Model calculation.

The Reduced Case presents speculated energy consumption values for the operation of a similar production pathway at commercial scale. Many energy inputs are simply not needed or would be much smaller in a continuous flow process. The Literature Model provides an estimate for the EROI of algal biocrude based on data that has been reported in the literature. In this way the Reduced Case is grounded on one side by the sub-optimal experimental data and on the other side by the Literature Model, which is largely comprised of theoretical data (particularly for biomass and lipids production from optimal algae).

What Colin discovered was that the EROI of the Reduced Case and Literature Model were 0.13 and 0.57, respectively. This shows that we have much to learn for the potential of making viable liquid fuels. Additionally, Colin’s calculations for the experimental set-up (and Reduced Case analysis) show that 97% of the energy output resides in the biomass, not the bio-oil. For his idealized Literature Model, 82% of the energy output was in the biomass.

While these results seem discouraging, we do not have much ability to put these results into context of the rate of development of other alternative technologies and biofuels. How long did it take to get photovoltaic panels with EROI > 1 from the first working prototype in a lab? We have somewhat of an idea that it took one or two decades for the Brazilians to get reasonable EROI > 1 from using sugar cane for biomass and biofuel production (Brazilian sugar cane grown and processed in Sao Paulo is estimated near EROI = 8).

I believe we need to strive to quantify EROI for new technologies even they are still in the laboratory stage. Perhaps some very early technologies and processes are even too early for estimating or measuring EROI, but algae biofuels are clearly in the mainstream of research given the $500 m investment by Exxon-Mobil into genomics firms searching for the ideal strains of algae. These ideal strains of algae might simply excrete hydrogen, ethanol or lipids such that all of the capital infrastructure and direct energy requirements assumed for collecting algae and extracting the lipids even in Colin’s Literature Model can be largely unnecessary. Let’s hope others join in in trying to assess the EROI of their experimental and anticipated commercial processes for alternative energy technologies.

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