BIOENERGY FOR EUROPE: WHICH ONES FIT BEST?

7.1 Country specific life cycle comparisons 111
Miscanthus versus light oil or natural gas for heat production – Denmark
Use of fossil fuels
Greenhouse effect
Acidification
Eutrophication
Summer smog
Nitrous oxide**
Humantoxicity**
* How to interpret the diagram:
Advantages for
biofuel
Advantages for
fossil fuel
Miscanthus vs light oil
Miscanthus vs natural gas
-1000 -500 0 500 1000 1500
Danish inhabitant equivalents* per 100 TJ
The figure shows the results of comparisons between complete life cycles where light oil (blue rows) or
natural gas (red rows) is substituted by Miscanthus for heat production. The unit refers to an amount of
100 TJ of heat. This is equivalent to the average heat requirement of about 4,700 inhabitants of Denmark
in one year or a Miscanthus production of about 1,100 ha/a.
Conclusion
The results show that both Miscanthus as well as light oil or natural gas have certain ecological advantages
and disadvantages, depending on the parameters given highest priority. Thus for example, Miscanthus
has significant environmental advantages over the fossil fuels with regard to the parameters
greenhouse effect and use of fossil fuels but on the other hand light oil or natural gas is superior with
regard to nitrous oxide, acidification and human toxicity. The other parameters show less significant
result in favour of fossil fuel. However, the data for human toxicity tend to have a uncertainty higher
than average, and should therefore not be included in the final assessment. (**For more information on
this and the other environmental parameters investigated see Chapters 3.3 and 3.4 as well as 4.1.2.)
A further assessment in favour of or against Miscanthus or light oil/natural gas cannot be carried
out on a scientific basis, because for this purpose subjective value judgements regarding the individual
environmental categories are required which differ from person to person. Whether Miscanthus is assessed
as better or worse than the relevant fossil fuels depends upon the focus and priorities of the decision
makers. If the main focus of the decision maker is for example on the reduction of the greenhouse
effect and the saving of energy resources, Miscanthus will be better suited. If on the other hand the parameters
nitrous oxide and eutrophication are deemed to be most important, then light oil or natural gas
would be preferred.