It’s a common assumption that bioenergy is a new green technology, or at least one that is a better alternative to current fossil fuels, but this often isn’t the case.
Many countries, like these, are building new generators to handle the increasing demand for electricity and to counter the prices and finite nature of fossil fuels. But do you know what bioenergy is?
Bioenergy has a vague definition “Bioenergy is energy contained in living or recently living biological organisms, a definition which specifically excludes fossil fuels.” Note here that without the word “recently” fossil fuels could fit into the same definition.
Sweden’s increase in bioenergy actually correlates to an increase in national GDP and a decrease in greenhouse gases. Their main source of bioenergy is forest residue, this is the unused parts of forest trees that the paper industry doesn’t want to use. They also process sewage sludge, household and industry biowaste (such as food), manure and landfill waste.
It is good to ‘recycle’ landfill waste in some way for obvious reasons, but also because methane from decomposing waste in landfills accounted for 3% of total greenhouse gas emissions in 1995 according to the European Commission.
Reducing greenhouse gases is clearly a good thing, and creating energy in the forms of liquid fuels, heat and electricity are also beneficial. Sweden uses so much waste that they need to import it from other countries. Other countries such as Italy actually pay Sweden to take their landfill waste and in return Italy gets a pile of ash, which contains heavy metals and harmful dioxins to be put in a landfill. This is actually a cheap way to get rid of the waste for other nations.
Despite the reduction in greenhouse gas emissions, the processes do still result in emissions at a lower level.
A possible game changer comes from Daphne Utilities in Alabama, where they have created a carbon-negative algae biofuel system that also treats municipal wastewater in the process. Locally, naturally occurring algae, sunlight, and wastewater are all that is required to create liquid fuels such as gasoline, and the water is almost clean enough to drink. As the process is still being developed for use on a larger scale, I don’t think we can accurately stick with the carbon-negative claim when taking into account the carbon emissions from the combustions of the fuels it creates, but it appears to be a move in the right direction.
Denmark is the world leader in incineration of household waste, burning 80% of their household waste. The inefficient process of burning waste has been labeled a “19th century practice which is clearly unfit for the 21st” by Zero Waste Europe. The process is criticized because it releases high amounts of pollution and greenhouse gases into the atmosphere. Denmark doesn’t use the same technology as Sweden and despite burning 80% of their waste, this only generates 20% of heat and 5% of electricity used.
Bioenergy has received a lot of criticism, particularly from the European Union, and laws have been brought in to regulate and limit its use. The problems are largely with biocrop use. A biocrop is a plant such as soy or palm which is grown specifically to turn it into energy.
“This legislation was supposed to ensure the EU does not continue to promote biofuels that exacerbate climate change and have a negative social impact but what has been agreed and voted today will not do so. It is a major missed opportunity.” said Green MEP Bas Eickhout on the cap.
“The 7% target should be seen as a first step in limiting crop-based biofuels.” said Marc-Olivier Herman, Oxfam’s EU biofuels expert.
Biocrops are criticized from a range of issues.
The EU claims that using land to grow biocrops results in increased food prices and deforestation as food crops compete for the same agricultural land.
“Converting rainforests, peatlands, savannas, or grasslands to produce food crop–based biofuels in Brazil, Southeast Asia, and the United States creates a “biofuel carbon debt” by releasing 17 to 420 times more CO2 than the annual greenhouse gas (GHG) reductions that these biofuels would provide by displacing fossil fuels.” – Land Clearing and the Biofuel Carbon Debt (2008)
The World Bank has estimated that food price rises may be ascribed to biofuels as much as 75%. (see graph)
The World Resources Institute claims that the world needs to close a 70% food gap between 2006 and the amount needed in 2050. They claim the gap would shrink to 60% if crop-based biofuels were phased out, or the gap could increase to 90% if biofuel companies reach their targets.
The report also states that for bioenergy to meet 20% of the world’s total energy demand by 2050, it would require at least double the annual harvest of plant material in all its forms.
It also mentions a comparison to solar power: “On three-quarters of the world’s land, PV systems today can generate more than 100 times the useable energy per hectare than bioenergy is likely to produce in the future even using optimistic assumptions.”
When bioenergy results in an increase in greenhouse gas emissions, an increase in food prices or an increase in deforestation, I don’t think we can consider it to be a green technology. But bioenergy doesn’t always have those problems.
There is no absolute answer about whether bioenergy is green because there is a problem with definition.
Chopping down a forest to burn it for heat falls under the same label as the carbon-negative algae biofuel generator. There are so many ways to create energy from biomass, some are good, some are bad, and they’re all called bioenergy. This is the problem.