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Tag Archives: biomass

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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Biomass battles

By Dave Elliott

The Dirtier than Coal report from Friends of the Earth, Greenpeace and the RSPB argues that burning trees would produce more CO2 net than burning coal, in part due to the delay before CO2 was reabsorbed by new planting. (See also my earlier blog on this topic.)

Dirtier than Coal refers to Carbon Impacts of Using Biomass in Bioenergy and Other Sectors: Forests – a report by North Energy Associates (NEA) and Forestry Research (FR), produced for the Department of Energy and Climate Change (DECC), which tried to answer the question: “Is it better to leave wood in the forest or harvest it for timber, other wood products (e.g. panel boards) and/or fuel?”. It concludes that: “Management of UK forests for wood production can contribute to UK carbon objectives, e.g. to 2050…Using wood for bioenergy can also reduce carbon emissions, compared to burning fossil fuels for energy…These results suggest that policy should support managing UK forests to produce wood for products and bioenergy.”


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Energy in the USA

By Dave Elliott

The boom in shale gas extraction may dominate the news headlines, but renewable energy is also moving head rapidly in the USA. It currently supplies about 15% of US electricity, if off-grid use is included, and the potential for expansion is very large. A new report from the US National Renewable Energy Laboratory (NREL), ‘The Renewable Electricity Futures Study’ (RE Futures), found that the US renewable resource base was sufficient to support 80% renewable electricity generation by 2050, even in a higher demand growth scenario. It also looks at a 90% option, with 700GW of wind and solar PV.

To accommodate this large variable supply input, there would have to be major upgrades to the grid and up to 100GW of balancing back up/ load shifting/storage. But NREL’s hourly modeling found that, with this backup in place, demand could always be met, even at peak times, although 8-10% of wind, solar, and hydro generation would need to be curtailed e.g. at times of low demand, under an 80%-by-2050 RE scenario, and more storage would be needed in the 90% scenario.


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Green Heat 2

By Dave Elliott

The governments new Heat Strategy review took on board many of the arguments for district heating, and even the use of solar, that previously had been rather marginalised. It identified pathways for the transition of the UK’s heat supply to low- and zero-carbon energy sources in the domestic and industrial sectors.

The Combined Heat and Power Association (CHPA) was delighted. It said that ‘the Strategy points the way to a major expansion of new district heating networks in towns and cities, driving a multi-billion pound investment programme in green infrastructure and creating an additional 40,000 jobs in construction and engineering’.


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Biomass limits (Part 2)

Liquid biofuels for transport, but also other types of biomass production and use, have been promoted as away to reduce greenhouse gas emissions, boost rural development and ensure energy independence. However this approach has run up against major constraints, including land-use and biodiversity issues. Moving to second generation non-food biofuels, and also biomass wastes, may help, as may tighter regulation (see my previous Blog–1.html

But there may also be clever approaches that avoid some of the land-use limits of biomass.

Perhaps the most obvious is to use biomass differently. Biogas production via anaerobic digestion (AD), e.g. of bio wastes, is widely seen as a good idea – coupled with using the gas grid for delivery. You can then use it for heating. But you can also use biogas in car engines. For example, it’s been claimed that methane through AD requires only about a quarter of the land area ethanol requires, and is a far more efficient fuel than ethanol, easily used in cars and trucks. There are certainly enthusiasts for it in the UK and elsewhere:
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Another option is to produce hydrogen by thermo-chemical processing of biomass/wastes, as proposed by Karl-Heinz Tetzlaff, possibly combined with CCS.

The hydrogen can be used for heating, possibly admixed with methane and delivered via the gas main; in fuels cells; or as a vehicle fuel direct. Or it can be used to make syngas /ammonia.

There are however some efficiency penalties involved with these various conversions. A PhD thesis by Anna Suess from Eindhoven Technical University looks at biomass as a CO2 saving technology. She compared synthetic natural gas (SNG), methanol, Fischer-Tropsch fuels, hydrogen and bioelectricity. Although she concludes that the overall practical resource is limited, the best option evidently proved to be converting biomass into electricity and using that to power electric cars. ‘First of all, biomass can be converted efficiently into electricity. Electricity can also be generated in smaller plants, which reduces the need for transport. And finally, electricity is a clean and efficient energy source for vehicles’. That certainly fits with the current vogue for an all-electric green energy future with cars run of electricity from renewable sources, but whether bio-conversion is better than electrolysis (e.g. using wind generated electricity) is far from clear- although you can store biomass.

However there are also more radical approaches. For example , “Breaking the Biomass Bottleneck”, a report by Henrik Wenzel (from Concito, a green ‘think tank’ in Denmark), suggest that we could upgrade biomass by hydrogenation, using hydrogen produced by the electrolysis of water, powered by excess electricity from variable renewables like wind. The report claims that you can react biomass with hydrogen ‘to produce hydrocarbons of much higher energy content and energy density than the original biomass. Moreover, using the biomass and the biogenic carbon from hydrogenation in central applications like heat and power , it is possible to collect the CO2 from the biomass and further recover and recycle it in a process here called Carbon Capture and Recycling, CCR. This will further multiply the use of the biogenic carbon from the biomass. Overall, upgrading and recycling biogenic carbon by hydrogenation and CCR, can approximately five-double our biomass potential for providing storable and high-density fuels and carbon feedstock compared to the presently applied technologies for converting biomass to fuels and feedstock.’

This sound wonderful- something for nothing, although, not really, since it can’t invalidate the laws of thermodynamics. But, the report notes, even with electrolysis losses, 1 Joule of wind can save 1 Joule of biomass, by upgrading it. However, the report adds ‘The total energy content of the biomass and the hydrogen is, of course, greater than that of the fuels on the output side. If, therefore, hydrogen is sufficiently good for the demanded energy services in question, there is no sense in taking a detour of producing the carbon based fuels from the hydrogen. The conversion from hydrogen to carbon fuels as energy carrier is only justified by the inherent differences in the properties and qualities of the two’.

So it’s end-use utility that matters, especially as it costs more, given the efficiency loses. But even so, the report claims that it makes sense. Not only go you get a valuable green fuel, you can also store it easily and help balance variable wind and other renewables, while using less biomass and less land. Moreover, if the biomass used is replaced consistently and sustainably, and you capture the CO2 produced when the fuel is burnt, then you have an overall net carbon negative system- although the report says that transport uses are less attractive, since then you can’t capture the CO2.

There are also versions of this idea which just use hydrogen produced from wind derived electricity and carbon dioxide from the atmosphere, to generate methane, methanol or some other synfuel. See for example

It would in effect create a carbon neutral fuel from the movement of and COs in the air, and it could be carbon negative if the CO2 was collected after combustion. Moreover, it avoids biomass land-use issues entirely. However air capture of CO2 still remains very expensive, so biomass looks a more likely carbon feedstock for the moment.

All in all though, there’s some clever green chemistry emerging. For more see:]

Another very ambitious approach involves using algae, or other biomass, grown in desert areas, possibly coupled with CCS. It’s been argued that, if algae is grown at the yields that the IEA Task Force bio-energy says is credible, then a land area the size of 24 % of Australia (in practice spread around Earth’s deserts) would produce 90,000 TWh/y which nearly equivalent to the current global final energy demand of 98,000 TWh/y. Moreover if some of that algae /biomass is used in CCS schemes then we would have a powerful carbon-negative energy technology: BECCS – bio-energy with CCS.

The Global CCS Institute has just produced a report which concludes: ‘there is a widespread unawareness of BECCS amongst policy makers, and also a lack of research and demonstration programs directed at the BECCS segment of climate mitigation measures. The insufficient efforts in research and deployment of BECCS are detrimental not only for the biomass industries, but for climate mitigation policies in general. Studies show that billions and trillions of Euros could be saved by including BECCS in mitigation portfolios. There are also large benefits to be gained in developing joint transportation and storage systems for fossil fuel CCS and BECCS, as this would increase economies of scale and lower the costs’.

One way to do this might be by growing algae in a Seawater Greenhouse As I’ve noted before, the first commercial SG scheme is up and running in Australia and more are planned around the world, possibly in conjunction with CSP technologies, to desalinate water. See

For food or algae production, as well as energy and water, you have to provide nutrients. One way to do this might be to stir up the sea-bed near the water entry point and suck in the sediment, then filter and dry it. Of course there are many uncertainties in relation to, for example, costs and impacts on fragile desert and marine ecosystems. However, the Dutch routinely use ocean sediment, allowing the saline content to drain back to the sea. Clearly, if this is to be done on any scale, we will need some detailed Life Cycle Assessments first.

Certainly many ‘greens’ are worried about the use of biofuels to keep the cars (and planes) going for a range of reasons.. See for example:

Moreover, in terms of electricity and heat production, many would see conventional flow renewables, like solar, wind, wave and tidal power, as a better bet, with fewer eco impacts: e.g. see Mark Delucchi’s biomass LCA studies: Ann. N.Y. Acad. Sci. 1195 (2010) 28-45 and Biomass and Bioenergy (2010), doi:10.1016/j.biombioe.2010.11.028

The debate continues, with the latest input being a fairly critical report from the RSPB: ‘Bioenergy: A Burning Issue’, which says the rush to build new power stations in the UK will mean that imports of the wood needed will have to rise from 13% to 68%- three times higher than the UK’s total current wood production. [

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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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Green energy for China

What happens in China, in terms energy use, is widely seen as a key to whether serious global climate impacts can be avoided or limited. China is relying heavily on coal but is also turning increasingly to non-fossil energy sources. Its nuclear programme often gets the headlines but in 2008 China had as much wind capacity in place as it had nuclear capacity – 8.9 GW. Of course, the relatively low load factor for wind (under 20%) meant that nuclear produced more energy – 68 TWh as against 13 TWh for wind. Moreover, new nuclear plants are planned, including fast neutron reactors to be supplied by Russia. In all, plans announced in recent years call for nuclear stations to supply 4% of China’s power needs by 2020, up from about 2% now, although of course its energy use is expanding rapidly, so that is more than a doubling in capacity. But wind has now more than doubled – installed capacity reached 25 GW in 2009, and a 2020 wind target of 150 GW has been mentioned. China’s wind programme is also moving offshore: it recently installed its first 3 MW 90-metre diameter “Sinovel” offshore turbine, the first unit of a 100 MW Shanghai Donghai Bridge demonstration project.

Certainly renewable energy, along with clean coal (i.e. with carbon capture) seems to be seen as a key way ahead. Chen Mingde, vice-chair of the National Development and Reform Commission, in comments quoted by the China Daily newspaper last year, claimed that “nuclear power cannot save us because the world’s supply of uranium and other radioactive minerals needed to generate nuclear power are very limited”. He saw the expansion of China’s nuclear power capacity a “transitional replacement” of the country’s heavy reliance on coal and oil, with the future for China being in more efficient use of fossil fuels and expanded use of renewable energy sources like wind, solar, and hydro.

China’s current target is to get 15% of its energy (not just electricity) from renewables by 2020, although this is likely to be raised to 20%. In addition to wind, it’s pushing ahead with solar as well as hydro and biomass. China’s hydro capacity is expected to nearly double to 300 GW by 2020. And a recent REEEP study suggested that 30% of China’s rural energy demand could be met through bioenergy. China already has 65 GW of installed solar thermal power, and the potential for expansion is significant (e.g. for large scale, concentrating solar power units in desert areas, feeding power by HVDC links to the cities). A 1GW prototype plant is planned.

PV solar is also set to expand rapidly. China is already the largest producer of solar cells globally and, although until recently most of them were exported (around 1 GW in 2007), the emphasis has now changed, so that the current national target of having 3 GW of capacity in place by 2020 could be exceeded by perhaps a factor of three. Looking further ahead, work in also underway on tidal and wave energy projects.

Some major integrated projects are also emerging. For example, Reuters reports that China is currently developing a demonstration zone in Hangjin Banner, with a planned 11,950 MW renewable-energy park, which, when completed, should have 6,950 MW of wind generation, 3,900 MW of photovoltaics, 720 MW of concentrating solar power, 310 MW of biomass plants and 70 MW of hydro/storage.

Some innovative new grid links are also being established, designed to deal with the problem that much of the renewable electricity resource is remote from mostly coastal centres of population. The new extended grid system could also help with balancing the variable output from some renewables. Modern Power Systems reports that Siemens Energy and China Southern Power Grid has started commissioning part of a High Voltage Direct Current (HVDC) transmission line, with a capacity of 5000 MW, covering a distance of more than 1400 km. It’s claimed to be the first HVDC link in the world operating at a transmission voltage of 800 kV. Commissioning of the second phase, and startup of the full system, is scheduled soon.

The Yunnan–Guangdong interconnector will transmit power generated by several hydro power plants in central China to the rapidly growing industrial region in the Pearl River delta in Guangdong Province with its megacities Guangzhou and Shenzhen. This system can, it us claimed, reduce the annual CO2 emissions that would otherwise have been produced by fossil-fuelled power plant by over 30 megatonnes.

In addition Modern Power Systems reports that there is the 800 kV Xiangjiaba–Shanghai link, on which ABB has been working with the State Grid Corporation of China (SGCC). It will be capable of transmitting 6400 MW of power from the Xiangjiaba hydropower plant, located in the southwest of China, to Shanghai – a distance of over 2000 km. It is claimed that transmission losses on the line will be less than 7%.

China is now the world’s largest carbon dioxide emitter and its energy demand is still rising rapidly, despite the global economic recession. However, in the run up to the COP 15 climate negotiations in Copenhagen last December, while not willing to commit to reductions in net emissions, China said it would cut its energy intensity (emissions/GNP) dramatically – by 40–45% by 2020. That’s not the same as reducing net emissions of course, but it would be a start. And if that is acted on, renewables would clearly play a major part.

China’s role at COP 15 has been much debated – essentially it seemed to want to protect its continued growth, and avoid imposed emission targets targets – much like the US. But, like the US, it also seems keen to be a leader in the move to green energy technology – perhaps becoming the “green workshop of the world” feeding the expanding markets for renewable energy systems around the world. In addition to exporting solar PV cells, it was even planning to build wind turbines for and in the US – although a US senator’s objections may have scotched that.

How rapidly China can and will green itself though is less clear. Certainly China has massive renewable resources: for example the wind resource is put at around 2 TW. And a new study by Michael McElroy and colleagues at Harvard and Tsinghua University in Beijing, published in the journal Science, has claimed that, in theory, wind power could meet all of China’s electricity demand by 2030.

That is very unlikely happen by then of course, but China is likely to become a major player in the green-energy revolution.

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Wood Pellets – Does a Resurgence in an old fuel Signal that Technological Innovation is Failing?

An article in the July 7th edition of the Wall Street Journal (WSJ) describes how the use of wood pellets is on the rise as a fuel for electricity in the EU. They are the “new Tulip” now being traded as a commodity on the Amsterdam energy exchange. In just looking up the price for industrial wood pellets, the price is hovering in the range of 130-140 €/MT (metric ton). With an energy content near 7,500 Btu/lb, this is similar to low rank (brown or lignite) coal.

With the well-written WSJ article referenced above, I won’t discuss the issue further here, other than to marvel that the use of wood is competing for the generation of electricity and heat with fossil and other modern renewable. Granted, the wood pellet stoves are much more controlled and efficient than your great-great-great-great-great-great-great-great (i.e. great8 to great10) grandfather’s wood burning stove. But this story is still a good example of technology struggling to overcome the limits of resources and moving back to a previous fuel. Unfortunately, we know that there are limits to the quantity of wood that can be replaced sustainably, but this is also an important feedback.

Over the last 300 years industrialized society has moved away from wood because the fossil energy resources had much higher energy density and concentration in mines and fields with oil and gas. Now industrialized society is moving somewhat (albeit on a very small scale) back to biomass in the form of these wood pellets for heat and electricity (often thrown into boilers with coal), but also including biomass for biofuels. This represents the struggle of “technology” to solve problems that society wishes to solve (in this case less greenhouse gas emissions) and the lack of focus of businesses to create substitutes for the services that primary energy resources (i.e. oil, gas, nuclear materials, biomass, sun, etc.) provide and that people want.

Unfortunately we have traditionally waited for the retrospective economic effects to tell us to return to a focus upon the value that energy resources and services provide to civilization. Data from the last 40 years shows us that people and the government focus upon energy costs when they become approximately 9-10% (at least half is for oil) of the gross domestic product of the US (for example see data at the EIA and chart in this paper by Charles Hall). Full data are not out for the last two years, but it appears as though we passed this threshold in 2007 and were likely well above 10% in 2008.

But this focus upon energy services has become, will become further, and should be center to discussions of economics. What percentage of GDP should we be spending upon energy? If this percentage gets too low, consumers and industry are not focused upon energy conservation and long term impacts. If this percentage gets too high (or too high too quickly) then general economic slowdowns tend to occur, mostly driven by oil prices in the last 40 years. Another question: How much we are in control of what this “energy/GDP” is or can be? The amount of energy obtained compared to searching and obtaining primary energy resources, or energy return on energy invested (EROI), is highly influential. If we get 50 barrels of oil when using the energy equivalent of 1 barrel of oil (e.g. EROI = 50) to find and extract that oil, then we have 49 barrels of oil to power the rest of the economy. If the EROI is 20, then this is significantly different. Less energy for health care. Less energy for education. Less energy for agriculture and food production. Etc.

We must understand to associate EROI with GDP much better than we currently understand. Otherwise, we won’t be able to foresee the longer term and very important implications of our energy policy and technology decisions. EROI must be used and understood as a measure of technical innovation.

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