Joe Beach
CSM Physics Department
1523 Illinois Street, Golden CO 80401-1887
Fax: 303-273-3919

Joe Beach CSM Physics logo


I am a part-time associate research professor in the Physics Department at the Colorado School of Mines. My primary employment now is Starfire Energy, a business that my wife and I started in 2007. I have a personal and professional interest in sustainable energy, and my research tends to reflect that.

Research Interests

I am currently working with professors Colin Wolden and Tim Ohno on a research project seeking to increase the efficiency of cadmium telluride (CdTe) solar cells. In particular, we are developing new processing methods to increase the cell's open circuit voltage. The efficiency of current polycrystalline CdTe solar cells is limited by a relatively low open circuit voltage (best cells are around 0.850 V) relative to the CdTe band gap (1.45 eV).

The vapor transport deposition system's source tube while it is heating. Faculty at CSM have been researching CdTe solar cells for over a decade. We currently deposit the CdTe absorber layer of the cells using a "vapor transport deposition" machine. This machine heats solid CdTe chunks in a quartz glass tube while flowing a carrier gas over them. The carrier gas moves the vaporized CdTe to a substrate, where it deposits as a thin polycrystalline film. A photo of the CdTe source tube being heated is shown at the right. The upper heater vaporizes the CdTe, and the lower heater keeps the tube downstream of the source hotter than the "dew point" of the CdTe vapor/carrier gas mixture so that the CdTe vapor does not deposit in the source tube. A method similar to this is presently used by First Solar to deposit CdS and CdTe films in their commercial CdTe-based solar electric panels.


I developed the class PHGN419 Principles of Solar Energy Systems. The course is a broad coverage of the photovoltaic technologies, how they perform, how they are made, and how they are used in "real world" applications. The course is part of CSM's minor program in energy.

"Hands-On" Solar Experience

A 1.6 kW solar electric array mounted on a home's roof In early 2007, my wife started Starfire Energy, which designs and installs solar electric systems for homes and businesses. I joined her in the business in late 2007, and I have found it to be very educational. It is one thing to grow and characterize cells on 3.7 cm x 3.7 cm substrates in the lab, but it is another thing altogether to take 1.5 m x 1 m polycrystalline silicon modules and make them into a high quality, durable system in the field. The work has given me a lot of insight into the research and products that are needed to assist the solar electric industry. The photo at the right shows the solar electric array that my wife and I installed on our home. It was a 1.6 kW array, and over the course of a year it generated about 100% of the electricity we consumed. We have since added one more panel to make it a 1.8 kW array, so it now produces more electricity than we use each year.