27.12.2012 Views

BIOENERGY FOR EUROPE: WHICH ONES FIT BEST?

BIOENERGY FOR EUROPE: WHICH ONES FIT BEST?

BIOENERGY FOR EUROPE: WHICH ONES FIT BEST?

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

7.1 Country specific life cycle comparisons 155<br />

between the three heating systems stems entirely from the fossil CO2 emissions at combustion. As the<br />

energy source of biogas consists mostly of methane, there is a double reduction of GWP compared with<br />

its reference system, since the latter emits not only methane during slurry storage but also fossil CO2 at<br />

gas combustion.<br />

300<br />

250<br />

200<br />

150<br />

100<br />

50<br />

0<br />

GWP 500 years (g CO2 eq./MJ useful energy)<br />

Processing & utilisation<br />

Agriculture/forestry part<br />

Fossil fuel life cycle<br />

Agricultural reference system<br />

RME Diesel Wood Heating oil Natural Gas Biogas Natural Gas<br />

Acidification – Switzerland<br />

All biofuels cause slightly more acidification than the fossil fuel systems compared (see diagram below).<br />

Although diesel has a higher sulphur content than RME, the agricultural part of RME is more<br />

decisive for the overall impact. The spreading of mineral fertilisers results in ammonia (NH3) – emissions<br />

which contribute to acidification. The differences between the wood, heating oil and natural gas<br />

systems are based on due to the different burning emissions, namely due to higher NH3 and HCl emissions<br />

of wood. Biogas burning emits a lot more sulphur oxides (SO2) than natural gas burning, which<br />

explains the higher score for the biogas system.<br />

2,0<br />

1,8<br />

1,6<br />

1,4<br />

1,2<br />

1,0<br />

0,8<br />

0,6<br />

0,4<br />

0,2<br />

0,0<br />

Acidification (g SO2 eq./MJ useful energy)<br />

Processing & utilisation<br />

Agriculture/forestry part<br />

Fossil fuel life cycle<br />

Agricultural reference system<br />

RME Diesel Wood Heating oil Natural Gas Biogas Natural Gas<br />

Eutrophication – Switzerland<br />

The score for RME is smaller than for the diesel system (see result table below) in spite of more leaching<br />

of nitrate (NO3 - ) and higher ammonia (NH3) emissions due to fertilisation. But the system expansion<br />

with soy beans gives such a large reduction that the overall result is in favour of the RME system.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!