9 terms:

Major Infrastructure Planning Unit (MIPU)

Advisory body to the Secretary of State on the determination of planning applications of large infrastructure projects (e.g. over 50 MW).

Marginal Abatement Cost Curve (MACC)

Graph showing costs and potential for emissions reduction from different measures or technologies, ranking these from the cheapest to most expensive to represent the costs of achieving incremental levels of emissions reduction.

Mechanical Biological Treatment (MBT)

A treatment process for waste involving breaking down mixed waste (e.g. by shredding) and removing any recyclable material. The remaining waste is then either composted, incinerated, digested (producing biogas) or sent to landfill.

Medium abatement scenario

The scenario for emissions reduction measures through the 2020s that is our best estimate of the appropriate level of ambition to currently plan for.

Methane (CH4)

Greenhouse gas with a Global Warming Potential of 21 (1 tonne of methane emission corresponds to 21 tonnes CO2e).

Mid-merit demand

Part of demand that is higher than baseload demand, occcuring less frequently but present in at least 20% of the hours of the year. For example, during the day (diurnal mid-merit) and throughout winter (seasonal mid-merit).

Minimum stable generation (MSG)

The lowest level of output that can be sustained by a plant at a particular point in time (given its technical operating limits). Usually expressed as a proportion of its rated capacity.


Action to limit the causes of climate change, principally by reducing sources (or enhancing sinks) of greenhouse gases.


Million tonnes.