Electricity isn’t costless; do your part to reduce carbon load

When you think of what services today are indispensable, electricity is at the top of the list. The simple movement of electrons through wire enables us to power large machines and provide communications — it seems inexhaustible! It works 24 hours a day, every day of the year (allowing for a few blackouts from weather events or equipment failures), and you hardly ever see smoke from an outlet. It would be an ideal form of energy if its source were not anchored in fossil fuels.

With its rich stores of coal and natural gas, Pennsylvania is a net exporter of electricity, 40 percent of which is still produced in coal-fired plants. On the plus side, the state is ranked second in the nation for electricity produced from a non-carbon source: nuclear. That is fortunate, as without nuclear, the state would rank higher in carbon dioxide emissions. As it is, Pennsylvania ranks third in the nation in total carbon dioxide emissions at 245 million metric tons.

I mention all of this to dispel the notion that electricity is a clean source of power. Instinctively we all know it’s not, but the utilities and producers have done a very good job of painting a thin green veneer over electric energy production, touting wind and solar in their portfolios. The fact is, 67 percent of the four billion-plus kilowatt hours of electricity produced annually in the United States comes from fossil fuels, and almost two-thirds of that is generated from coal. Wind and solar power combined account for less than five percent of the total power production in the United States.

It takes energy in some form to produce electric power. Pennsylvania has a trove of energy-dense and relatively clean-burning anthracite coal. It takes about one pound of coal to produce a kilowatt hour of electricity. The coal has an energy content of 13,625 Btu. The kWh that pound of coal produced has an energy equivalent of 3,412 Btu. You can see the problem. There is that tremendous amount of energy going in, but much of it disappears in heat and mechanical energy losses before it hits the wires. Once the electricity is in the transmission grid, there are additional losses from resistance in the wires, transformers and switch stations. Much like a steam system, it takes considerable energy just to keep the grid powered before the first item is plugged into an outlet. Without nuclear, renewables and some imports — from Canada mostly — we would be burning a lot more coal.

The current level of technology imposes real limits on the power of the wind and sun to provide for all of our electric needs. Wind turbines have to be sited where the wind is fairly constant. Those locations tend to be distant from where the power is needed. Solar panels are effective when the sun shines, but require a substantial amount of space to provide even a modest level of power. By one calculation, it would take an installation covering thirteen acres — roughly the area of green space between Parrish and the railroad tracks — to provide one third of the power we use on a typical summer day; at night, virtually no power would be provided. By their nature these sources are inconsistent — for that reason, fossil-fuel generators are in stand-by to make up for sudden drops in the grid. It’s tantamount to having your car running in the driveway in the event that you want to drive somewhere later.

With such a bleak  picture, there must be something we, as an institution, can do to reduce dependence on electricity. Electricity accounts for more of our institutional carbon contribution than our direct burning of fossil fuels. It’s critical that its control the use. With the deregulation of the electricity market, cost has become a variable. Carbon is a constant. Although we do purchase wind energy credits to offset our use of electricity, we can’t lay claim to being carbon-neutral on that front. We’re not off the grid. We don’t have an extension cord routed from a wind turbine directly to the college, and we do have a responsibility to acknowledge that what we use has an impact, regardless of the source.

The primary tool for reducing our power requirement is conservation. It can be as simple as your finger flicking off unneeded lights or as technical as variable frequency drives to control motor loads. Unseen motor loads account for a very large proportion of the electricity the college uses. Electric motors are found in every heating, ventilation and air conditioning system, providing the seasonally appropriate flow of fresh air, heating and cooling. Lighting, the most obvious power draw, accounts for another large piece of the pie; however, but the proliferation of computing power and everything that goes into office and communication systems accounts for a growing proportion of energy needs built into modern buildings.

We have made progress. The college’s first step in conservation was investing in a Siemens building management system in Kohlberg Hall 18 years ago. That direct digital control system, which has expanded to all but a few buildings, enables us to track and control many of the lights and mechanical systems in buildings on campus. With the information it has provided, we have been able to gradually drive down our overall power use from its peak in 2005 at 17.1 million kWh to 13.6 million kWh in 2013. It doesn’t read like much, but when you consider the college added over 276 thousand square feet of new building space between 2001 and 2013, added a 600-ton chiller and renovated hundreds of square feet of additional space without a corresponding increase in electricity use, the reduction is pretty remarkable. The level of control we practice does have impacts. Rooms in most of the academic buildings are individually scheduled for HVAC and no air conditioning or heat is provided if they are not scheduled for use.

We have been transitioning gradually to more efficient lighting systems. LED light quality has improved dramatically in the past five years and we have taken advantage of that. Sharples was our first major application of the technology; we reduced the power requirement to one third of the old incandescent lamps, and the LED lamps last years longer, freeing up work hours. LEDs are being used in more spaces like the List Gallery in LPAC, the atrium area of McCabe, Parrish and 101 South Chester. We’re currently experimenting with LED tubes to retrofit existing fluorescent fixtures.

I still believe in the power of the human finger to turn off the lights. McCabe has been a notable success in power reduction using the ability of the human finger to turn lights on. Tom Cochrane, our utility manager, observed that the stacks were normally lighted for the 18 hours a day the building is open, but were largely devoid of people for most of the day. With the advice and consent of College Librarian Peggy Seiden, we installed stack switches. The difference has been eye-opening. Overall, the change reduced McCabe’s kilowatt hour load by nearly 200 thousand kWh annually, eliminating at least 80 tons of carbon contribution.

We have the potential to reduce electric power use even further in existing buildings with lighting modifications and equipment changes, but we are also faced with the inevitable growth that will increase our power requirements. Hopefully, new technologies will diminish the impact, but going forward, we have to be prepared for difficult decisions and major investment to minimize our carbon load.

One comment

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    Josh Hallquist says:

    Brilliant piece — I’ve often wondered why we talk so much about recycling and environmental justice and then walk out of the room with the lights and projector still on. The 200k kWh savings from behavioral changes in McCabe alone is stunning — to contextualize that, I just left a job at an energy efficiency nonprofit in marketing, and that scale of project would have been one we touted publicly as a model success story.

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