I have a few thoughts on this:
- The consideration of RECs is certainly controversial, and subject to some interpretation. In my opinion, you can only consider RECs to be a direct offset like this if you can ensure that they are local and benefitting the grid that you are consuming electricity from. If your local grid is relatively dirty, and your purchased RECs are supporting a local project that reduces emissions on that local grid grid, then I think this calculation method is valid. If you are purchasing RECs that support a project in a different region that does not directly support your local grid, then it depends (this would potentially not be a valid way to calculate consumption, depending on who you ask). This also does not get into the whole notion of how grid emissions vary over the course of a day.
- If you are comfortable with the source of your RECs (and that they are reducing emissions on the grid that your university is connected to), then yes, this calculation for electricity would work as an estimate of electricity emissions
- Are there any additional natural gas or other fuel loads to consider? I would expect that some university buildings use natural gas either because they are not connected to the steam plant or because they have other process loads
- For decarbonization over time, I would consider using NREL’s Cambium data, which provides grid emission factor rates projected to 2050 (assuming emissions reductions)
- For steam, I’ll give you the frustrating answer of ‘it depends’ - If the EPA emission factor assumes the same method of steam production (e.g., natural gas-fueled vs. coal vs. …), then this would serve as a valid high-level estimate, though it wouldn’t take into account the efficiency of your steam plant. The best estimate for a steam emission factor would be from measuring the fuel consumption of your heating plant and multiplying that by the appropriate fuel emission factor (e.g., natural gas, coal, …) rather than applying the factor for steam heat, which doesn’t take your university’s unique conditions into account.
I hope this is helpful!
Best,
Matt
P.S. I spent 10 years as an energy engineer, performing energy audits, modeling, analysis, and design review on a large number of projects, including some university and district-level projects.