Sustainability’s a huge topic. And higher education is an industrial sector not renowned for the agility of its participants. So where do you start greening a campus, and how?

To the extent that there’s an orthodoxy in this emerging field, it goes like this:

1. Energy conservation
2. Energy efficiency
3. Renewable energy
4. Emissions offsets

To start, conserve all the energy you can with the campus you’ve got. It’s what economists call “short term optimization.” Use what you have, as efficiently as possible. And “what you have” refers to buildings, not light bulbs. Change light bulbs. If necessary, change light fixtures. Change heating and cooling setpoints and schedules. Do the best you can with what you have, and generate some savings.

Ideally, you can use the savings which come from energy conservation to fund (or at least subsidize) some of the items lower on the list. Realistically, though, on most campuses that’s easier said than done. I know it’s so at Greenback U, where I work. More on the challenges (and on Greenback U) in a later post.

Second, when you add to your campus (OK, if you add to your campus), make the new space as energy efficient as you can afford. At today’s energy prices, you’re not likely to over-invest in insulation. Or lighting efficiency. Whatever additional money you invest will be paid back in a few years, sometimes less. After that, the savings are all gravy.

But recognize that you can’t grow your way to carbon neutrality. So long as your existing buildings continue to operate in their current mode, they continue to put out CO2, just like always. Don’t get too hung up on “energy intensity” or similar metrics. Add an efficient new building, and your CO2 per square foot under roof goes down, because it’s an average. But add that same efficient new building, and your total CO2 emissions go up, not down.

The biggest paybacks in energy efficiency come from rehabilitating space or replacing space. And “replacing” implies that the old space goes away. It gets knocked down or otherwise decommissioned. It stops emitting.

Energy conservation and energy efficiency are at the top of the list, because the cleanest energy is also the cheapest energy — it’s the energy you don’t have to pay for because you never use it. “Negawatts beat megawatts,” and all that. Energy conservation saves money in the short term. Energy efficiency saves money in the long term. Each of them is financially pretty easy to justify, at least at the institutional level.

Conservation and efficiency, however, each have two dimensions. There’s the infrastructure -- what we call “physical plant” -- and there’s how people utilize that infrastructure. The social dimension of conservation and efficiency is harder than the technical dimension, but the social dimension may be more important in the long run.

You see, if your campus is committed to achieving carbon neutrality (for instance, if your president has signed the PCC), conservation and efficiency by themselves won’t get you there. They might get you half-way, or three-quarters of the way, but they can’t do the whole job by themselves. That’s where renewables and offsets come in.

When you get your energy consumption down to a reasonable minimum -- or down to the point that further reductions would be cost-prohibitive -- then you’d like to use renewable energy for the remainder. Renewables are clean, they don’t emit greenhouse gases during their production processes, they’re easy to like. However, there are practical constraints to renewable energy, at least in the foreseeable future. More on that (again) later.

And for the energy that you can’t avoid using and can’t get in some renewable form, offsets are the only remaining option. Simple example: for now, I have a significant daily commute, and I can’t afford a zero (or even near-zero) emission vehicle. So, as a patchwork solution, I’ve arranged to offset the emissions from my driving. Colleges and universities can offset emissions, too. Given their resources and scale of operations, they have better offset options than I have as an individual. (More on that, guess when!) But offsets are the last resort, not the solution.

Since both renewables and offsets cost (not save) money, the campus community has to really back the effort. That’s why building social support -- helping all sorts of people to “get it” -- is so important even while you’re focusing on conservation and efficiency. Changing people’s habits will increase the impact of conservation and efficiency measures, and that’s a good thing. But the changed attitudes and expectations which result from changed habits are going to be absolutely essential if we’re ever going to be serious about steps 3 and 4.

Got questions about sustainability? Drop me a line at g.rendell@insidehighered.com