Transcript Biomass
Laura Wood Definition Biomass is all plant and animal matter on the Earth's surface. Harvesting biomass such as crops, trees or dung and using it to generate energy such as heat, electricity or motion, is bio energy. In many ways biomass can be considered as a form of stored solar energy. The energy of the sun is 'captured' through the process of photosynthesis in growing plants. Characteristics Biomass material properties and characteristics are quite varied, depending on the plant species, the nature of the resource material and its moisture content , which can range from around 10% for straw to even 95% for sewage sludge material. Properties of biomass fuels are defined by their physical structure, weight, volume, density and ash content. Eucaliptus clone Brazil Rapeseed field UK Poplar plantation Croatia Algae – USA Sustainability Using biomass as a fuel means that carbon dioxide (CO2) which was absorbed from the air while the plant was growing, is released back into the air when the fuel is burned. The system is said to be carbon neutral. Providing the balance is maintained between the plant growth and biomass use, the system is sustainable and helps combat climate change. Benefits 1) 2) 3) Employment – Bio-energy can significantly contribute to employment (direct, indirect and induced) at local, regional and national level. Social Cohesion - Social cohesion may be enhanced by organising and running a localised and renewable-based energy supply system, and quality of life may be substantially increased Security of energy supply – Britain is not dependent on Europe for biomass energy unlike it is for some of fuel. Costs • Could contribute a great deal to global warming and particulate pollution if directly burned • Still an expensive source, both in terms of producing the biomass and converting it to alcohols • On a small scale there is most likely a net loss of energy-energy must be put in to grow the plant mass Case Study Belgium, Suez In 2002, the Belgian utility Electrable decided to convert a 50 year old coal-fired power plant into one firing only biomass Electrabel aimed to: • Manage its carbon dioxide emissions; • Encourage the production of electricity from renewable energy sources; • Obtain 300,000 green certificates that allow Electrabel to fulfill the obligation established by the Walloon Region and avoid paying penalties of some € 100 per lacking green MWh; • Create the possibility of offering customers green electricity; • Recycle the residual raw materials from forestry (the cultivation of forest trees for timber or other purposes); • Diversify the fuels used to supply energy; • Save fossil fuel reserves; • Increase the share of green electricity from 15% to 18% within Electrabel Group. Case Study Cont…. The modification of this site has had a substantial impact on the surrounding communities and those involved in supplying the plant with wood pellets. It has: • Created direct (local) employment on site for at least 10 years (duration for the grant of green certificates); • Created indirect employment and economic development (forestry, wood pellets producer, shipping companies); • Improved the quality of the local environment by reducing emissions in the air and road traffic required for waste product disposal; • Recycled an industrial site, thereby maintaining local electricity production and creating the option to supply green electricity; • Recycled the residual products from forestry, up to 350,000 metric tons per year; • Avoided CO2 emissions of around 500,000 metric tons per year; • Saved some 280,000 metric tons of coal annually; Summary 1. 2. 3. 4. 5. Biomass is considered a form of stored solar energy. The characteristics of biomass are quite varied Carbon neutral and therefore sustainable Has many benefits such as social cohesion, security of energy supply and employment. Also has costs such as contribution to global warming, expensive source and net loss of energy.