Track Emissions for Stationary Assets

Learning Objectives

After completing this unit, you’ll be able to:

List the key fields on a stationary asset environmental source record.
Explain how to specify values for key fields on stationary asset energy use records.
Show a simple calculation of emissions on a stationary asset energy use record.

Take Stock of Your Buildings

Stationary asset environmental sources are used to represent all buildings and data centers associated with a company. Let’s look at how Sam handles this for NTO. Since all of NTO’s stationary asset records come with a few key fields, Sam creates a record for the NTO Headquarters and reviews and populates the key fields.

A stationary asset environmental source record showing details for NTO Headquarters Miami.

Let’s take a deeper dive into these fields and what they represent.

Field	Description	Impact on Calculations
Carbon Emissions Scope Allocation	The object that specifies the GHG Protocol scope of emissions for different fuels. Each fuel type has its own scope allocation record in the Carbon Emissions Scope Allocation Values object.	This field helps the user specify the scope to which the emissions from each fuel is allocated.
Refrigerant Emissions Factor	The object that holds the global warming potential (GWP) for cooling refrigerants, such as CFCs, HFCs, and HCFCs used in stationary asset sources. You can create one record per refrigerant type.	To properly calculate tCO₂e from refrigerant leakage, the refrigerant’s GWP is multiplied by the quantity of refrigerant leakage.
Electricity Emissions Factor Set	The object that holds a range of information that's relevant to calculating the scope 2 emissions generated from electricity. The GHG Protocol provides two methods for tracking scope 2 emissions: the market-based method and the location-based method. There are fields specific to both of these methods in the electricity emissions factor set.	Yearly datasets from sources such as Emissions & Generation Resource Integrated Database (eGRID) website can be uploaded to accurately calculate electricity-based emissions in a specific postal code.
Other Emissions Factor Set	The object that holds predefined emissions and conversion factors for emissions resulting from use of natural gas, propane, and on-site diesel use. While in the other emissions factor record, you can define the global warming potential values for CH₄ and N₂O, in the associated other emissions factor set item records, you can specify values for different fuel types, such as gasoline, LPG, or biodiesel.	All individual emissions and conversion factors for sources that are not included in the electricity grid or scope 3 data types are captured as part of the Other Emissions Factors.
Regional Building Energy Intensity	Lookup to a building energy intensity record from the Commercial Buildings Energy Consumption Survey (CBECS) data. The CBECS is a national sample survey that collects energy usage information on commercial buildings across the USA. The energy usage data serves as a reliable and publicly available standard, and is preloaded in Net Zero Cloud. The value is automatically populated when the country is the United States, the postal code is valid, and the total floor area is populated in the record.	NTO can use the CBECS building energy intensity data to plug energy use gaps in the data of commercial buildings (more on this later).

Energy Use for Stationary Assets

Buildings and warehouses at NTO use electricity, diesel for backup generators, and refrigerants for cooling. Each of these require separate energy use records associated with the same stationary asset source.

Within energy use records, Net Zero Cloud automatically calculates many of the fields based on energy use data and emissions factors.

Three energy use records associated with a stationary asset environmental source record.

Data for Key Fields

Sam works to create the energy use records to allow for emissions calculations. He looks at the information within an energy use record, one section at a time.

General Information

On a stationary asset’s energy use record, information like the total and occupied floor area and whether the asset is company-owned helps with calculations. Sam can also specify the stationary asset for which energy consumption is being recorded, the start and end dates of the energy consumption, and the corresponding stationary asset carbon footprint record.

General information, such as building details, reporting period, and references to the associated asset and carbon footprint on a stationary asset energy use record.

Consumption

Depending on the type of fuel for which an energy use record is created, this section helps Sam define the following.

Fuel type: There are multiple fuel types for which you can enter energy consumption, including Electricity, Diesel, Natural Gas, and Propane.
Fuel consumption unit: Multiple units of measure are supported natively in Net Zero Cloud corresponding to the different fuel types that are supported.

Fuel consumption information on a stationary asset energy use record.

Emissions Factors

If the emissions factors are specified on the stationary asset environmental source, they are automatically inherited by the associated energy use records. Thanks to the flexibility of Net Zero Cloud, Sam can also override the values on each energy use record if he needs to.

Associated emissions factors for electricity, fuel, and refrigerants on a stationary asset energy use record.

Supplemental Emissions

Sam can also specify supplemental emissions for each scope to manually adjust emissions, if needed. These are used in the calculated total emissions.

Supplemental emissions information on a stationary asset energy use record.

Grid Mix

The grid mix values on the energy use record are calculated based on the grid mix percentages specified in the associated electricity emissions factor set record. If he needs to, Sam can override the values for location-based and market-based grid mix on an electricity emissions factor set record based on the information he gets from the suppliers for NTO’s buildings in a specific postal code.

The market-based grid mix depends on the electricity that organizations have chosen to purchase from specific suppliers and takes supplier-specific emissions rates into consideration.
The location-based grid mix depends on the emissions intensity of the local grid area where the electricity usage occurs.

Location-based and market-based grid mix information on a stationary asset energy use record.

Renewable Energy
Renewable energy displays the quantity of electricity that’s generated from renewable sources. Sam can specifically allocate electricity generated from renewable sources in the Renewable Energy Type and Allocated Renewable Energy fields. The basis for the renewable energy calculations is the allocated renewable energy value entered on the energy use record and the market-based grid mix percentage on the electricity emissions factors record.

Renewable energy information on a stationary asset energy use record.

Emissions
This section displays the autocalculated emissions in tCO₂e by scope corresponding to the entered energy consumption in the stationary asset energy use record.

Autocalculated greenhouse gas emissions values on a stationary asset energy use record.

A Few Calculations Explained

Now that Sam has explored the key information on an energy use record for a stationary asset, he tries to understand how the emissions are calculated. Sam creates the following energy use records for the NTO Office Headquarters Miami stationary asset environmental source record.

Stationary Asset Environmental Source	Stationary Asset Energy Use	Fuel Type	Fuel Consumption Details
NTO Headquarters Miami	Monthly Electricity Bill Jan	Electricity	1000 kWh
	Monthly Fuel Bill Jan	Diesel	1000 Liters
	Q1 Refrigerant Bill	Refrigerant	10 kg

Calculation of Electricity Related Emissions

The United States - US-TX - electricityMap 2019 emissions factor record specifies the following.

CO₂e Emissions Rate for Location Based Emissions Factors = 396.78 g/kWh
Location-Based Coal-Mix Percentage: 20%
Location-Based Gas-Mix Percentage: 47%
Location-Based Nuclear-Mix Percentage: 11%

Emissions factor details on an electricity emissions factor set record.

Let’s see how the energy values are calculated on the stationary asset energy use record Monthly Electricity Bill Jan.

Scope 2 Location-Based Emissions (tCO₂e) = Electricity consumption (in kWh) * Emissions factor (g/kWh) / 10^6 (tCO₂e conversion factor)

= 1000*396.78/1000000 = 0.3968 tCO₂e

Furthermore, here’s how the information is calculated for the Location-Based Grid Mix.

Location-Based Electricity from Coal (kWh): 20% of 1000 kWh = 200 kWh
Location-Based Electricity from Gas (kWh): 47% of 1000 kWh = 470 kWh
Location-Based Electricity from Nuclear (kWh): 11% of 1000 kWh = 110 kWh

Greenhouse gas emissions results and grid mix data on a stationary asset energy use record for electricity.

A similar approach is followed to calculate market-based electricity emissions by referring to the market-based grid mix percentages.

Calculation of Diesel Related Emissions

The Fuel Conversion Factors - DEFRA EPA 2018 factor set record specifies the Global Warming Potential (GWP) values.

GWP of CH₄: 28
GWP of N₂O: 265

The OEFSI-0000006 factor set item record specifies the following.

Fuel Type	Calorific Value	Supplied tCO₂e Emissions Factor	CH₄ Emissions Factor	CO₂ Emissions Factor	N₂O Emissions Factor
Diesel	15 kWh/L	12.45 tonnes/mWh	3.00	73.96	0.06

The consumption of diesel (1000 Liters) is first converted to its kWh equivalent using its calorific value, which is 15 kWh/L.

Total Fuel Consumption = 15000 kWh (1000*15)

Next, this value is multiplied by the Supplied tCO₂e emissions factor and divided by the conversion factor.

Scope 1 Emissions (tCO₂e) = Supplied tCO₂e Emissions Factor * Total Fuel Consumption/1000

= (12.45*15000/1000) = 186.75

The autocalculated Scope 1 Emissions (tCO2e) value for Diesel on a stationary asset energy use record.
Calculation of Refrigerant Related Emissions

Lastly, let’s check out how emissions are calculated when the fuel type is Refrigerant. The Sulphur hexafluoride (SF6) - IPCC AR4 2007 refrigerant emissions factor record specifies the Global Warming Potential as 22,800.

Here’s how the emissions calculation shapes up.

Scope 1 Emissions (tCO₂e) = GWP * Fuel Consumption(kg)/1000

= 22,800*10/1000 = 228

Greenhouse gas emission results on a stationary asset energy use record for Refrigerant.

In the next unit, Sam creates a carbon footprint for this stationary asset and learns more about the calculations. Let’s follow along with him.