Considering using North American woody biomass for renewable electricity production? From next year, generators who fail to comply with UK government sustainability criteria will lose financial support.
A scientific calculator has been developed by the UK government Department of Energy and Climate Change (DECC) that investigates the impact on carbon emissions of biomass sourced from North America to produce electricity.
Bioenergy is expected to contribute significantly to the UK’s target for renewable sources to represent at least 15% of total energy consumption by 2020 (as required by the EU Renewable Energy Directive 2009/28/EC). The government’s Bioenergy Strategy published in 2012 made clear only bioenergy from sustainable sources should be used.
It has been estimated that by 2020, between 3.4 and 7.5% of the UK’s projected energy consumption will be generated from biomass, and the UK will require 12.9 to 23.5 Modt/y of solid biomass for energy, of which 9.0 to 16.0 Modt/y will be used for electricity generation.
In addition, under the Climate Change Act of 2008, the UK must reduce its greenhouse gas (GHG) emissions by at least 80% on 1990 levels, by 2050.
LCA (life cycle analysis) can be used to estimate the GHG emissions associated with the delivered bioenergy.
DECC’s sustainability criteria for biomass feedstocks supported under the Renewable Obligation (RO) (published August 2013) states that by 2020, electricity from solid biomass subsidised by the RO must be proven to generate electricity with a GHG emission intensity under 200 kg CO2e/MWh1 (DECC, 2013a), calculated based on the LCA methodology set out in Annex V of the EU Renewable Energy Directive (2009/28/EC).
This intensity is lower than that of electricity generated from fossil fuels in the UK (e.g. ~ 437 kg CO2e/MWh for electricity from natural gas, ~ 1018 kg CO2e/MWh for electricity from coal; DUKES, 2013; DEFRA, 2013), but higher than other renewables (e.g. 3 to 41 kg CO2e/MWh for electricity from wind; Turnconi et al., 2013).
The Renewable Energy Directive LCA methodology considers the emissions from the cultivation, harvesting, processing and transport of the biomass feedstocks. It also includes direct land use change where the land use has changed category since 2008, e.g. from forest to annual crop land, grassland to annual crop land. However, the Renewable Energy Directive LCA methodology does not account for changes in the carbon stock of a forest, foregone carbon sequestration of land, or indirect impacts on carbon stocks in other areas of land.
DECC now has the following core resources available:
1) Report – life cycle impacts of biomass electricity production in 2020
This is a Report that aims to:
* quantify the woody biomass resources that are likely to be available for pellet production from forests in North America by 2020;
* estimate the GHG emission intensities (in kg CO2e/MWh delivered energy) of using these resources for electricity generation in the UK, accounting for the impacts omitted by the EU RED methodology (emissions or sequestration from carbon stock changes on the land, foregone carbon sequestration, and indirect impacts); and
* estimate the Energy Input Requirements (EIR) (in MWh energy input per MWh delivered energy) of using these resources for electricity generation in the UK and compare to other electricity generating technologies. The energy input is considered to be energy carriers which are ready for final use, e.g. electricity, diesel, natural gas, fuel oil. The primary energy of the biomass is not included as an energy input in the calculation, just as the energy in the wind, sunshine, or nuclear fuel is not included in the Energy Input Requirement for wind, solar and nuclear technologies.
The Report is here.
2) Calculator – BEAC (Biomass Emissions and Counterfactual) Model – the calculator itself, which can be used by developers to help make sure they are sourcing their biomass sustainably.
BEAC is here.