If local governments purchase steam or heat from a combined heat & power (CHP) facility, they must calculate the associated Scope 2 emissions.
The LGO Protocol provides three methodologies for calculating emissions from CHP purchases:
Recommended Approach: Produce Stream Method
- Obtain the following emissions and power & heat information from the:
a. Total emissions (CO2, CH4, and N2O) based on fuel input information.
b. Total electricity production, based on generation meter readings.
c. Net heat production. - Determine emissions attributable to net heat production and electricity production by using Equation 6.21.
- Calculate emissions attributable to the local government’s portion of heat and electricity consumed by using Equations 6.22 and 6.23. To use these equations, the electricity and heat consumption of the local government must be obtained.
- Convert to units of carbon dioxide equivalent and determine total emissions using Equation 6.24.
Alternate Approach 1: Simplified Method for Heat Purchases
An alternate approach is using the methodology for quantifying Steam and District Heating Purchases, which is for calculating emissions from imported steam or district heating from conventional boiler plant. Conventional boiler plants produce steam and heat less efficiently than CHP facilities, so this will result in an over-estimation of Scope 2 emissions.
Alternate Approach 2: Simplified Method for Electricity Purchases
Another alternate approach is using the methodology for quantifying purchased Electricity from the grid. Because grid-average electricity may also be produced less efficiently than electricity produced at a CHP facility, this may also result in an over-estimation of Scope 2 emissions.
