Tag: drax

Counting on … day 79

4th April 2024

Bioenergy can also be obtained from trees – the timber is burnt to  either as direct form of heat from a stove of fire, or in a power station to  drive steam turbines that generate electricity.  Burning timber is the most common form of bioenergy used in the UK. Whilst it can be claimed that only waste timber is used – cuts and shavings from timber plants – the reality is that power stations such as Drax import timber which already starts to add to its carbon footprint. International rules imported timber is zero carbon as the emissions are counted in the country where the trees are harvested. In fact these emissions are often not recorded at all. And whilst the timber arrives here as preformed pellets, the timber intact comes from whole trees  from mono culture plantations or from virgin forests.

In reality burning timber as a bioenergy is not a zero carbon option. The carbon stored in the timber is going to be released at some point in the future but if that tree is left to grow, and in its own good time, die, that carbon is locked in longer. Even better as the tree decays in its natural environment it will take years to decay during which time it will provide a habitat for a great variety of different plants and creatures.  Further a large part of the carbon will be absorbed into the soil, again storing it away. If on the other hand the tree, having been felled, is used to make doors, floor boards, paper, furniture etc so the carbon is locked away for many more years to come. 

For further reading – https://www.rspb.org.uk/helping-nature/what-we-do/influence-government-and-business/nature-protection-and-restoration/bioenergy

Is burning wood for energy worse for the climate than coal?
Biomass Basics

Carbon capture and storage CCS for the ongoing burning of fossil fuels to generate energy – https://www.theguardian.com/environment/2024/mar/26/tone-deaf-fossil-gas-growth-in-europe-is-speeding-climate-crisis-say-activists?CMP=Share_iOSApp_Other

Counting on … day 78

3rd April 2024

Biofuels are fuels derived from biomass such as plant material, food waste, algae, or animal waste. There are two forms of biofuel – 

“Bioethanol is an alcohol made by fermentation, mostly from carbohydrates produced in sugar or starch crops such as maize, sugarcane, or sweet sorghum. Cellulosic biomass, derived from non-food sources, such as trees and grasses, is also being developed as a feedstock for ethanol production. Ethanol can be used as a fuel for vehicles in its pure form (E100), but it is usually used as a gasoline additive to increase octane ratings and improve vehicle emissions.

And “Biodiesel is produced from oils or fats using transesterification. It can be used as a fuel for vehicles in its pure form (B100), but it is usually used as a diesel additive to reduce levels of particulates, carbon monoxide, and hydrocarbons from diesel-powered vehicles.” (https://en.wikipedia.org/wiki/Biofuel)

Brazil is the largest producer of bioethanol and the EU is the largest producer of biodiesel. 

Both forms of biofuel differ from fossil fuels in that they are produced from organic materials being grown now as opposed to using organic materials that were decomposing millions of years ago.  

Both produce greenhouse gas emissions but less than do fossil fuels. Biofuels may be made using only waste materials, but often are made from crops that have been specifically grown for this purpose. This may have the affect of diverting land that would otherwise be used for growing food, or may involve deforestation to create new crop lands. 

Drax power station which burns timber as a biofuel to generate electricity uses wood pellets. Although wood pellets can be made from waste wood, most of the pellets that are burnt at Drax are made from whole trees that were once growing in virgin forests in South Carolina and British Columbia. These are then imported to the UK. For more information- https://www.bbc.co.uk/news/science-environment-68381160