How do the MJ used to produce a lb. of milk change depending on net metering and Renewable Energy Credits (RECs)?

Selling or retaining RECs does not impact the overall energy use measure (in MJs) but does impact whether the energy is categories as “renewable” or “nonrenewable”. If the REC for that renewable energy is sold, then that energy is placed in the “nonrenewable” category. If the REC is retained, then the energy stays in the renewable energy category.

Net metering does not impact the total MJs, but like REC ownership, it affects where it is placed in terms of renewable versus non-renewable.

Do you have energy factors used to convert to MJ?

Here are the energy factors used in FARM ES:

electricity east* 14.07772 MJ primary / kWh electricity
electricity west* 11.10698 MJ primary / kWh electricity
diesel 155.4316 MJ primary / gallon diesel
biodiesel 68.16122 MJ primary / gallon biodiesel
fuel oil 180.5243 MJ primary / gallon fuel oil
propane 104.001 MJ primary / gallon propane
natural gas 139.5043 MJ primary / therm (= ccf) natural gas
gasoline 164.8766 MJ primary / gallon gasoline

* North America is comprised of two different major power grids, east and west. The data source for the electricity factors only offered factors for east and west at the time that the FARM ES model was created.

Does diesel use for spreading manure or scraping the pens need to be accounted for?

Diesel use for manure spreading does not need to be entered into the energy use section of FARM ES– the model already makes assumptions about manure spreading energy use within its feed emissions factors in the model.

Diesel to scrape the pens is considered a dairy activity and should be included in the energy use section of FARM ES.