Service Communautaire d'Information sur la Recherche et le Développement - CORDIS

WP(8) Energy analysis of energy wood production and utilisation

- This work package deals with emergy analysis at: 1) Country level and 2) process level emergy analysis of energy wood production and utilisation chains.

- Methodology for emergy evaluations at country level and for process level are presented.

- Three examples for emergy evaluations at country level are included:
-- Emergy evaluation of economy in Sweden for year 2002, by Hagström & Nilsson, 2003.
-- Emergy evaluation of economy in Bulgaria for year 2001, by Markov, 2004.
-- Emergy evaluation of economy in USA for year 2000, by Rodrigues, (2002).

Also the most widely used energy wood production chains in Sweden (ChainA: Bundles of logging residues, ChainB: Wood chips of logging residues, and ChainC: Loose logging residues)combined with a virtual energy wood utilisation plant for CHP production.

- The emergy evaluation procedures are detailed and the sources of information are documented. MS-Excel workbooks are elaborated, these can be used as information-gathering templates and as tools for easier preparation of all emergy evaluation tables.

- The main results are the transformities of the main products of the investigated chains standing biomass at the forest site, harvested wood at the forest site, wood chips at the utility site (ready for conversion) and heat and power ready for distribution from the utility site.
- All chains starts from one and the same from alder and spruce forest site and eneds with one and the same CHP plant.
- The transformities of the products of chain A in seJ/J are, respectively: 9496.05, 16247.48, 19697.86, and 32937.20.
- For the products of chain B these transformities are, respectively 9496.05, 16247.48, 23405.03, and 37547.29.
- For the products of chain C these transformities are, respectively 9496.05, 16247.48, 19066.23, and 31879.34.

Key innovative features:
- The transformities of the products of the investigated chains are compared as well with the transformities of the fossil fuels at the production site: coal (48720 seJ/J), natural gas (58464), crude petroleum (67536), and refined petroleum products (80472).
- It is obvious that even the final product of chain B - heat and power produced from alder spruce chips - has lower transformity than the transformity of the most efficient fossil fuel (coal) at the production site.
- Emergy analysis is a new method for analysis and understanding of the combined work of the nature and the society.
- It provides a more holistic basis for evaluation of the real value of all economic results of human activities, products and services, as well as all material resources and energy sources from nature used by mankind.
- It provides important information, which might influence the human behaviour and relationship to Earth and Earth s resources.

Current status:
- The emergy analysis provides information on how effective the economy is, and helps the policy makers to understand, from a holistic point of view, the impact of their decisions on the environment.
- Woody biomass contains available energy - potential energy, which can do work.
- By burning of woody biomass a small part of the energy of the chemical bounds of its substances is used to form the products of combustion and the rest is released and transferred into heat
- The available energy of woody biomass can be measured in energy units, usually in Joules (J).
- In contrast, emergy is a measure of the energy that has already been used to build up woody biomass.

Use potential:
- Emergy is a record of all types of previously used energy, which is only a small part of the energy bound in a product. Emergy estimates the magnitude of the work involved in the production of that material.
- Emergy is evaluated usually in emjoules (emJ) or solar emjoules (seJ).
- The quotient of a product's emergy content divided by its energy content is defined as its transformity.
- The unit of transformity is seJ/J, so the transformity is not a dimensionless ratio.
- The more energy transformations there are contributing to a product, the higher is its transformity.
- A unit of woody biomass has a higher transformity level than the sun and rain that contributed to produce it.

Expected benefits:
- It is clear advantages of biofuels for production of heat and power in comparison with the fossil fuels, in addition to the neutral CO2 load to the environment they provide a more efficient way for utilisation of the energy supplied to our civilisation for free from the Nature solar insolation, gravitation and deep Earth heat.

The results are disseminated by 1) Using the Echaine web-page, 2) Partners presentations at by Echaine organised international workshops (Bulgaria and Russia), 3) Partners presentations at national and international seminars and workshops, 4) Scientific papers.

Reported by

8 Kliment Ochridsky Boulevard
1000 SOFIA