By Huck Fairman
A riddle: Which local entity finds 12,000 people working daily in its buildings and roaming its walks and roads? Which entity generates power from a fighter jet engine, has installed a large solar array, and calculates a self-imposed a carbon tax? Which entity first used steam heating in the 1860s, and still does, and is planning to reach 1990 emissions levels by 2020, and Net Zero emissions by 2050? And which calculates all energy innovations by their long-term financial costs and benefits but also through a sense of stewardship toward our environment?
Well, perhaps not the most challenging of riddles. But what is impressive about this entity, our local university, is the unusually extensive deliberations, indeed investigations, that it has undertaken in choosing various energy production and distribution systems.
Before installing its substantial solar array on the other side of Carnegie Lake, and running the electric lines underneath the lake back to the campus, Princeton University spent seven years calculating the technological details and options, along with the long-term costs/benefits. Before deciding to construct and operate its complex cogen power plant and the several connected systems, the university — particularly its Facilities Department, directed by Ted Borer — studied the matter for 10 years.
What allows the university to be this thorough and patient? Mr. Borer explains that it comes from the university’s awareness that it has been, and will be, here for a long time. And with this comes a recognition that it is both dependent on the environment and a steward of it. To take all of this into consideration, along with the long-term financial calculations, requires a vision and determination (or spine,) to see it through. Although Mr. Borer didn’t explicitly state this, it is an approach that could benefit other school systems, towns, states, and the world — as on Earth Day 2016 representatives from around the globe met to sign the Paris Climate accord.
While the university is quick to acknowledge that it is fortunate in being able to afford these innovative systems, it also takes unusual pains to insure that the systems are “doable,” and that over time they will save the university significant operating costs. Beyond those requirements, the university’s decisions are in part guided by selecting technologies that others can adapt for their own needs. The institution does not see itself as existing in an ivy tower but as a participating member of the community. Aware that science has warned that we need to change our energy systems, the university embraces this responsibility, saying, “How can we not join in? And where possible, lead?”
The university is housed in 150 buildings, and many of its new labs and computing systems are energy intensive. To power this community, it has put much thought and evaluation into the best means. (It stopped using coal in 1960.) One option, as with most homes and businesses, is to have individual heating and cooling units in each building. But that is patently inefficient. More economical and efficient is having several power plants that can distribute electricity, heating, and cooling to districts on campus, and that is what the university has done.
While the university normally buys 50 percent of its electric power, and all of its natural gas, from our utility, to which it stays connected, it generates the other 50 percent itself. And it has the capacity to generate a much higher percentage.
But because the cost of utility (or grid) electricity varies, the university can choose the lowest cost of the two sources, switching from one to the other. If the utility grid goes out of service, as it did during Hurricane Sandy, the university’s systems can keep the school operating.
In addition, the school’s systems produce 100 percent of its cooling and heating needs. And to acknowledge the real cost of its energy and heating/cooling systems, it calculates a hypothetical carbon tax to factor into those costs.
Generating half of its power needs saves considerable money, particularly when utility rates rise. But, additionally, because the university is a high volume customer, it has been able to contract with the utility to be charged lower prices at times of low demand — an arrangement that is not available to homes and businesses. It is these several savings that the university recognized would make the initial systems investments pay off.
No less a benefit is that its systems and purchasing strategy enable the university to reduce its carbon footprint. Part of the efficiency and environmental benefit from generating much of its own power is that while utilities typically can deliver to their customers only between a quarter and a third of the energy generated, the university’s systems can deliver 70 to 80 percent of its generated energy.
How is this possible? Why the discrepancy? Much of this efficiency comes from its cogeneration plant. When utilities generate electricity, the heat and gases also created are released into the atmosphere. While Princeton’s cogen plant likewise uses natural gas to produce electricity, with its gas turbine — basically a jet engine that generates not only electricity, but considerable heat (up to 950 degrees F.) — that heat, instead of being released and wasted, is captured and used to produce steam, which is then piped to university buildings for heating.
Adjacent to the cogen plant sit two other buildings. One is a chilled water plant that cools water, when utility rates are low, which is then stored and used to cool campus buildings when utility rates are high. That chilled water is stored in the thermal storage plant before it is piped to the buildings.
Also contributing, of course, to the university’s self-generated electricity is its large solar array which produces 6 percent of the university needs. That array was installed on top of the 1970s Carnegie Lake dredgings which are unsuitable for other uses or construction.
Still another money-and-energy-saving technology has been adopted for three new building complexes: the Lawrence Apartments on Alexander Road, the new graduate town houses between the lake and Faculty Road, and the new Arts and Transit complex at University Place and Alexander. There, ground-coupled heat pump systems run water pipes into the earth where the temperature is a steady 55 degrees, before returning that water to the buildings and maintaining the 55-degree temperature.
And yet, even with all of these state-of-the-art systems, which the Facilities Department is constantly upgrading and maintaining, Ted Borer cautions that it is still better financially and environmentally, to reduce usage and conserve power than it is to rely on these new technologies.
Given, however, that our complex economies and lifestyles do and will require electrical power, heat, and cooling, it is encouraging, even inspirational, to see the degree of thought, long-term planning, and innovation that the university utilizes for its own benefit, but also as an example for homes, businesses, and communities across the nation, and, as the climate accord signing reminds us, around the world.
Huck Fairman is a Princeton author who writes SOLUTIONS about environmental issues.
