When it comes to emissions Scopes, which is the worst? I get asked that a lot. I think it is sort of subjective and depends on where you are standing and what “worst” you are defining.
Scope 1 emissions are produced at your property using a flame or combustion. A gas-powered golf cart or a natural gas hot water heater would be your scope 1 emissions sources. There is a big push right now to eliminate Scope 1 through electrification. From a “worst” perspective, I do not like it because my personal beef with gas ranges and heaters in the unit is their tendency to emit carbon monoxide. From the “this can kill you now” perspective, it can be viewed as the worst. However, from a difficulty of solution perspective, it might not be the worst because you can swap these devices for other things. Your golf cart could be electric (making it Scope 2), or you could use a heat pump for heating the unit, or an electric or solar thermal hot water heater. So, if you are defining “worst” to mean hardest to address, those emissions are not the worst.
Scope 2 emissions may not always be viewed as the worst because they represent the gateway to renewables. We know how to swap electricity produced by nonrenewable sources to renewable sources. We can swap Scope 2 sources to photovoltaic, wind, hydro, waste to energy, or other renewable resources. However, if the electricity currently coming to you from the grid is generated using coal, you might be cleaner for the environment by using Scope 1 for your property until you can swap directly to renewable energy. So “worst” can change very quickly depending on how your energy is generated. For example, a few years back a friend of mine said he was going to do his part for the environment by avoiding purchasing an electric car. When I questioned his logic, he simply stated that, in his area, electricity was produced with coal so, from an emissions standpoint, using a gas-powered car was cleaner for him than electric.
Speaking of cars, let us talk about Scope 3. Scope 3 is all the stuff you cannot necessarily control. Resident or tenant behavior is Scope 3, as is trash production, and transportation to and from your property in all forms (delivery trucks, trash trucks, team commutes, resident commutes, etc.). Some folks view it as the worst because you can influence it but not control it. It also can be seen as the worst because it is the hardest to measure. It can be a hodgepodge of electricity and combustion. It might theoretically be cleaner than Scope 1 production, but (I am talking about your automobiles) unless properly ventilated can be life threatening and bad for the environment.
So, to define what is worst is going to depend on where you are and what are your personal criteria for “worst”. From my perspective, worst is what can kill us the fastest. We can rank other threats from there. If you can eliminate the risk of carbon monoxide poisoning first, then tackle emissions, that is my ranking for worst. However, that might not be yours.
