CO2 Emissions: Biomass

Current emissions

The table below shows the CO2 emissions associated with the gas and electricity that would be replaced by the CHP system.

 

Tonnes CO2

CO2 saving from reduced industrial gas use

6228

CO2 saving from reduced industrial electricity imported from the national grid

9513

CO2 saving from reduced domestic electricity imported from the national grid

2148

Total CO2 annual saving from energy offset

17890

Table 1: CO2 saving from energy

The payback period for the embodied CO2 is estimated as 1 year, which is equivalent to 17890 tonnes CO2 .  Over the 20 year life cycle this works out as 894 tonnes of CO2 per year.  The emissions associated with both the production and transport of the wood chips are based on estimates from the Royal Commission on Environmental Pollution and are expected to be 138 tonnes of CO2 per year. 

 

Tonnes CO2

Embodied carbon of system installation (over 20 years)

894

Embodied carbon of wood chips

120

Emissions from transport of wood chips

18

Total annual CO2 emissions of CHP system

1033

Table 2: Embodied CO2 of the system

Total CO2 saving

The total annual saving CO2 associated with this scheme is 20583 tonnes, which represents a saving of 29%  on the original CO2 emissions of the community.

 

Tonnes CO2

Total CO2 annual saving from energy offset

17890

Total annual CO2 emissions from CHP system

1033

Total annual CO2 saving from installation of system

16857

Table 3: Annual CO2 saving

Cost per tonne CO2 saved

Capital cost per tonne CO2 saved over 20 years

£525

Annual saving per tonne CO2 saved excluding ROCs

£8

Annual saving per tonne CO2 saved including ROCs

£59

Table 4: Cost per tonne of CO2 saved