A simpler, cheaper technology for solar panels

PULLMAN, Wash. – I recently pulled some weeds in my yard. Sometimes I’m glad to have a little simple work where I can see progress, even if the effects of my labor are only temporary.

I can only do a little bit at a time, having to take it slow due to arthritic knees. But one thing about pulling weeds in August stands out even when taken in small doses: it’s hot work.

With the sun beating down, warming the whole nation, it’s easy to wonder if solar power will some day replace fossil fuels as our mainstay energy resource. That could be a wonderful development from a couple of perspectives:

1. It could make the U.S. more energy independent

2. it could reduce the amount of carbon dioxide we produce by limiting the coal, natural gas and petroleum we burn. That’s why, from a climate perspective, solar power could be very helpful.

Some efforts to harness the sun depend on capturing energy to do things like warm up cold water. A few houses are designed to collect energy from the sun during the winter to “passively” warm rooms with southern exposures.

Those are good and valuable efforts, but to my mind they pale in potential significance to work aimed at converting the energy of sunlight into electricity.

Electricity is a wonderful form of energy. We can do almost anything with it, ranging from cooling our houses in the summer via air conditioning to heating them in the winter with electric heaters. Electricity runs washing machines and light bulbs and can power everything from stoves and vacuum cleaners to computers and radios.

If we could engineer an economical and environmentally friendly way to convert sunlight into electricity, we might find ourselves on Easy Street with respect to the economic and political costs of our national power needs. 

The solar panels you’ve seen on top of RVs prove every day that electric power can indeed be generated by sunlight. I once had a single panel I bolted to the top of my humble 1972 travel trailer. I about doubled the value of my investment in the trailer when I added that panel to it.

I used the setup to charge a car battery I put on the tongue of the trailer. During the day, electricity flowed into the battery. At night I used the battery to power a single high-efficiency light bulb in the trailer that allowed me to read after dark. 

Solar panels, sometimes called photovoltaic panels, are still relatively expensive. They also generally contain some elements that are not environmentally friendly. In short, there’s room for improvement in solar cells and that fact has many engineers working on them.

Recently there’s been some good news about a new kind of panel that might really make a difference to the economics and the environmental impact of solar panels. The news comes from Oregon State University. Using ethylene glycol, the active ingredient in anti-freeze, engineers have made progress researching what’s called a continuous flow process to making “thin-film” solar cells.

With a continuous flow approach, things look good in terms of being able to scale up the process to industrial production at low cost per unit produced. Perhaps best of all, the panels would be based on a mixture of copper, zinc, tin and sulfur. These are all fairly common and cheap elements compared to those used in most solar panels today.

“We need technologies that use abundant, inexpensive materials, preferably ones that can be mined in the U.S. This process offers that,” said OSU’s Greg Herman in a press release.

Using common metals could help us get away from the use of indium in photovoltaic panels. Indium is both rare and pretty costly. And it’s mostly produced in China. In contrast, the metals in the new type of solar cell can all be mined in the U.S. and are much cheaper than indium.
A great deal about the energy landscape would be changed if we find a way to harness the sun in economically and environmentally attractive ways. Here’s wishing the best to researchers across the country who are working to crack the solar nut.

Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. This column is a service of the College of Agricultural, Human and Natural Resource Sciences at Washington State University.