Fields of light

Big box stores at the Arena Hub Plaza in Wilkes-Barre
Township, built on the former site of culm banks.
Imagine this scene covered in solar panels.

When I was at the University of Scranton I would sometimes take lunch with my friends in the second-floor cafeteria at the the Gunster Center, also known as the Student Center. The North wall of the cafeteria was all windows, and it overlooked the campus's tennis courts. In Winter the courts would go unused, and after a heavy snowfall they would present themselves as a field of gleaming white snow - until, inevitably, someone got around to creating rude graffiti with footprints. But I digress.

One day I was having lunch - or maybe it was dinner - with some friends near these windows, and I looked out at the snow-covered tennis courts. I looked out at the dazzlingly bright scene, amazed at how much sunlight was being reflected. How much solar energy is falling on that area? I wondered. And who knows, maybe I did some paper napkin calculations. But I got to thinking about the photoelectric effect, and what went into manufacturing solar cells*, and I realized that while this is a magnificent and amazing way of taking sunlight and converting it into a usable form of energy - in this case, electricity - nature had been doing the same thing for a very long time through the amazing process of photosynthesis. What if, I wondered, we could find a way of getting plants to convert sunlight directly into fuel material? Well, plants do that already; you can burn most plants and release energy stored in their tissues. Or you can ferment some plants and, through a series of chemical and biological steps, create alcohol. But other plants create oils, or oil-bearing seeds and nuts from which the oil could be extracted. What if we could breed a plant that could use energy from sunlight to produce oils with characteristics suited to our fuel needs?

That was probably when I noticed that the footprints in the snow on the tennis courts spelled a rude word in 20-foot-high letters, and pointed it out to my friends.

*****************

The tennis courts ceased to exist years ago, replaced by a multi-story library. The Student Center was demolished earlier this year after a new one was built to take its place.

The need to find new sources of energy is greater now than it was during my lunchtime reverie in the mid-80's.

Northeastern Pennsylvania, like many places, is gradually becoming a land of big white boxes. I work in one, and others cover the mountainsides like huge, flat snowbanks. Several major highways run through NEPA (I-80, the great East-West corridor; I-81, a North-South corridor second perhaps only to I-95; and the Pennsylvania Turnpike), we are in close proximity to New England, New York, New Jersey, and Philadelphia; and real estate prices are very reasonable (up slightly from "cheap.") These factors have combined to make us an ideal location for warehouses and distribution centers. In addition, we have the usual suspects when it comes to malls and big-box stores.

This is less of an environmental disaster than you might think. This is coal country, and coal mines produced enormous quantities of waste rock - slate mixed with coal that could not be separated out economically.** And these were piled up in great artificial hills called culm banks. Culm banks, some covered with groves of trees, some large enough to alter regional wind patterns, were a major feature of this area until a few years ago. Now many of the culm banks are gone, hauled off to be reprocessed for any usable coal, the remnant used as fill...somewhere. Replacing a culm bank with a revenue-generating mall or warehouse or big box store is not necessarily a bad thing.

But there is something inherently wrong with this new landscape of flat buildings and flat parking lots. When seen from above it resembles a lifeless desert, with a few trees and grassy areas thrown in for traffic control purposes. Sunlight rains down and is absorbed by the asphalt of the parking lot and the tarpaper (or whatever the coating is) of the flat roofs. Cars heat up, buildings need to be cooled. Energy is wasted in the form of both incoming sunlight and electricity used to run cooling systems.

What if we were to cover everything in solar panels?

Solar panels have some drawbacks. They are expensive. They are heavy. They are relatively inefficient. The electricity they generate costs more , for the moment, than electricity generated by remote sources. All these things can change.

There are other practical problems. Big box roofs are not designed to handle the weight of several hundred solar panels covering every square inch of available space, especially not when these panels are laden after a heavy snowfall. A parking lot roofed by solar cells would present new hazards to drivers, many of whom (as I have noted before) should not even be allowed to drive a shopping cart. And there is always the hazard of making a big, long-term investment in a technology that is superseded in its lifetime by something vastly better.***

Could there be financial advantages to investing in photovoltaic electrical generation on surfaces that are otherwise just solar heat sinks? Absolutely - if the surface is going to be around long enough to recoup the investment. What is the life expectancy of a big-box store? A mall? A parking lot? What is on the horizon in photovoltaic technology? How will photovoltaic-generated electricity costs compare to, say, coal-fired power plant-generated electricity, particularly as deregulation of the cost of electricity takes effect?

In the meantime the photons rain down from the Sun and fall on the roofs of the malls, and the roofs of the warehouses, and the roofs of the big boxes, and the surfaces of the parking lots, and the interiors of the cars parked on them. How much longer can we afford to let this energy go to waste?

*I only knew this theoretically; it would still be several years before I was working for a solar cell manufacturer in Delaware after a brief but humiliating run in grad school.

**Often the task of separation was carried out by children, called "Breaker Boys." This practice ended well before the Knox Mine Disaster ended coal mining in NEPA on January 22, 1959.

***I wonder how smart the folks who invested in big-screen TVs back in the mid-90's, when they cost so much that some people were having them built into their walls so they could have them rolled into their mortgages, feel today.