University of Vermont

Green Dorm

Next Steps

by Ryan Darlow '12, UVM Clean Energy Fund Intern

 

The feasibility study has finally moved on from solar PV. Reports were created for all feasible buildings on campus, as well as adjacent parking lots. CHA will also be contributing a ground mount report for various locations around campus. In total over 80 buildings were surveyed as well as 30 parking lots. Based on those surveys around 4.5 MW could be installed on the roof tops of UVM’s buildings as well as around 2 MW on the various parking lots.  In 2011 UVM consumed over 65,000,000 kWh of electricity, which means if every single one of these projects is completed then UVM could offset more than 10% of its annual electricity consumption. The potential for sizeable ground mounted installations around the Miller Research Farm and Bio-Research Complex could significantly improve that number. UVM clearly has a significant potential for solar PV.

My investigation into UVM’s potential for wind power has also progressed significantly. I received a very brief report for Wind Analytics that shows the approximate average wind speed at 30 meters at nine different locations spread throughout campus. This report identified all nine locations as class 1 wind which means an average speed of 11.6 mph or slower. The averages range from a minimum of 10.1 mph around central and athletic campus to a maximum of 10.9 mph south of the Miller Farm.  Generally wind turbines require class 3 wind speeds or better to offer significant payback which means the average wind speed needs to be above 13 mph. Since the energy of the wind is based on the cube of the velocity a 13 mph wind has more than twice the power as a 10 mph wind. Based off the data I received, wind power is likely not very feasible on campus.

This is result not at all surprising. Most of campus is tightly packed with buildings and trees which make a horrible location for most wind turbines. The few larger open spaces are the fields to the south of the Bio Research Complex and Miller Research Farm. Consequently those are the locations with the highest average wind speed. However all of those locations are completely surrounded by trees from South to West to North. This means that all of campus is in a location of high turbulence called the boundary layer. There is a wind boundary layer surrounding the entire earth due to an engineering principle called the no-slip condition. This rule states that at the location where a fluid flow (blowing wind) meets a solid (the earth) the velocity of the fluid must be zero. The earth’s boundary layer ranges from a few feet above the surface of the ocean, to hundreds and thousands of feet in urban environments. Turbulence greatly decreases the quality of the wind, which means that the average wind speed decreases and the efficiency at which a turbine can extract power from the wind is diminished. This is why campus is not very feasible for wind turbines.

There are some smaller wind turbines that claim to take advantage of some micro climates created in urban settings that yield strong wind patterns. These wind turbines are called building mounted turbines. They claim to be able to capture the upward flow of air caused by wind hitting the side of a tall building and using that to generate power. These are often vertical axis turbines which claim to be more resistant to the losses generated by low quality turbulent flow. Many of these claims and designs are still theoretical. These are multiple companies that produce these turbines; however none have been able to prove their claims to be true. This means as more research is completed parts of UVM’s campus may become more feasible for wind power.

This internship has been a great start as I look towards my personal next steps in a field of renewable energy. I have been exposed to many renewable energy technologies that are all related to my interests. Despite my previous knowledge about vertical axis wind turbines, I have learned a lot about the feasibility of installation. It has been very interesting learning how to survey for solar PV, and geothermal. It is a skill that I will use when marketing myself for a job, and knowledge I will be using in my future. Feasibility studies are both interesting and exciting to me. They allow businesses and organizations to learn about their renewable energy potential, which can be very exciting. Learning about the infrastructure that large organizations such as UVM use daily but are often unseen is very interesting. Another strong appeal of the study is being able to work outside for part of the day. I am definitely a visual person so measuring a structure outside before returning to a computer to complete some analysis is very rewarding. I hope to continue to use what I have learned during this internship in my career.