Proceedings

A study commissioned by the Scottish Environment Protection Agency (SEPA) indicated that
from a total of 13.7 million tonnes of waste produced in Scotland every year; 9.6 million
tonnes were deemed to be technically suitable for processing in an Anaerobic Digestion or
thermal treatment plant to obtain energy.

It was calculated that the energy content of the biowaste could supply sufficient power to
meet the needs of over 2 million of Scotland’s 2.4 million households. It is estimated that 741
Anaerobic Digesters and 228 Thermal Treatment plants it would also provide in the region of
7,200 direct jobs.

There was also the additional benefit of displacing Carbon dioxide (CO2) through the use of
biowaste. The report recommended that Combined Heat and Power (CHP) should be the
technology of choice and that there would be the potential to offset 2,463,171 t CO2
equivalents through the use of energy from biowaste – this is approximately 4.5% of
Scotland’s total emissions.

The report which formed the base data for the JE Jacobs study into the development of
policies for the treatment of tertiary treatment of commercial and industrial waste (C&I),
concluded that that energy recovery through Combined Heat and Power systems (CHP)
either by anaerobic digestion or energy from waste (EfW), is the preferred option for the
tertiary treatment of C&I wastes. Mixed residual waste to CHP is the most favourable option
followed by segregated biomass to anaerobic digestion with CHP. Policies that drive waste to
combined heat and power facilities are therefore recommended.

KEY WORDS
AEA Technology; Anaerobic Digestion (AD); Combined Heat and Power (CHP); Energy from
Waste (EfW); JE Jacobs