Tag: timber

Counting on … day 89

18th April 2024

How Renewable are Renewables?

Many things are renewable as in they can be naturally replaced – timber is a renewable resource in that for every tree used/ consumed, another tree can be grown. Water is a renewable resource in that once used it can be recaptured and reused: this might be through the natural water cycle of evaporation, transpiration, condensation and rainfall, or through collecting and cleaning waste water for further use. Fish for use as food is a renewable resource – this supply of food is maintained through the natural reproductive processes of the fish. 

However the renewability of things isn’t necessarily limitless. 

If oceans are overfished, the rate at which new fish are born and mature will not keep pace with the rate at which fish are caught. Eventually there will be no fish.

If trees are felled faster than the rate at which new trees reach maturity – which can be  40 to 150+ years depending on the species – the landscape will become deforested. 

If an ecosystem is not maintained, more can be lost through evaporation in a locality than falls as rain. Without forests in the middle of large continents, rainfall in these areas would be negligible reducing the landscape to desert. If rainforests are cleared, rainfall in those areas will be diminished reducing the landscape to bare earth.

Solar energy is a renewable energy source – the sun is constantly producing heat – as is wind, as the earth’s weather system continues to be generate wind. (Sometimes resources such as sunshine, wind, tides and geothermal energy are known as perpetual resources).

 But whilst solar and wind energy are constant/ renewable, the means by which we capture that energy may not be as readily replaced. Solar panels that convert the sun’s energy into electricity are  made of non-renewable minerals – silicon, silver, aluminium, and copper. Wind turbines that capture the wind’s energy converting it into electricity are made of large amounts of non renewable materials such as steel and carbon fibre.

The source of the energy is renewable but not always the means by which we capture the energy.

Here is an interesting blog describing how solar panels are made – https://blog.ucsusa.org/charlie-hoffs/how-are-solar-panels-made/

and wind turbines – https://blog.ucsusa.org/charlie-hoffs/how-are-wind-turbines-made/

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 1.217

16th November 2023  

The lead author of the study into the health (or rather threatened health) of our woodlands, published in  ‘Forestry: An International Journal of Forest Research’, is Dr Eleanor Tew, head of forest planning at Forestry England and visiting researcher at the University of Cambridge. Whilst the threat of a collapse of our woodland ecosystems is possible, it is not inevitable. “We do have time to make a difference, and there is a lot we can do to make our forests more resilient,” said Tew, who described the paper as a “call for action”… The forestry industry has to plan in advance …. an average conifer in a plantation can take up to 60 years to reach maturity, and a broadleaf up to 150 years. “Forestry has always been about planning for the long-term, and we’re at a time of huge change,” said Tew. Solutions [could] include increasing the diversity of tree species within a wood, planting trees of different ages, promoting natural regeneration and managing deer populations.”(1)

The Forestry Journal published advice from ConFor the forestry’s  industry wide body  to improve tree planting:-

  • a coordinated UK-wide approach to the 30,000-hectare target, currently not in place;
  • planting targets to be clearly linked to delivering other policy objectives – mitigating climate change, supporting biodiversity and delivering rural jobs and growth;
  • clear targets to use more home-grown wood – the UK is the second highest global net importer of wood after China, and using more wood will lock up more carbon (2)

Growing timber for domestic use – eg construction, furniture making etc seems logical. Maybe we can help by specifying such products if we are making such purchases. 

(1) https://www.theguardian.com/environment/2023/nov/08/uk-forests-face-catastrophic-ecosystem-collapse-within-50-years-study-says-aoe?CMP=Share_iOSApp_Other

(2) https://www.forestryjournal.co.uk/news/18834822.confor-calls-urgent-action-tackle-uk-tree-planting-failure/