Sunday, November 22, 2009

HRES Solar Thermal


On Friday, Andrea Ruedy Trimble, Jessica Parks, Carol Healy, Zhen Wu, Mitch Hunter, and Fady Ghattas of the Harvard Office for Sustainability took a tour of the solar thermal installations on 472-474 Broadway and 20-20a Prescott Streets in Cambridge. Bjorn Storz of Harvard Real Estate Services lead the tour. There are 14 flat plate collectors on the two roofs and they are expected to provide 30 to 40% of the domestic water demand. The solar planels collect heat through a glycol loop which is pumpted to plate frame heat exchangers in the basements. From there a water loop transfers heat to storage tanks. Finally, another set of plate fram heat exchangers transfers the heat to pre-heat the domestic water, which receives additioanl heating from natural gas boilers. The installation is expected to reduce GHG emissions by 13 MTCDE per year and save 2,300 therms of natural gas.

The systems performance is being tracked real time and available on the web. The public is invited to track the performance of the system by visiting http://harvard_prescott.heizwerk.at/ and logging in with username "frei" and password "frei". Solid Solar, the manufacturers, are continuing to monitor the system from Germany and making slight tweeks to the controls to optimize its performance.

Everybody on the Office for Sustainability staff enjoyed the tour and hopes to see more such installations on roofs around Harvard and elsewhere.

Read more.

Wasted Energy or Hospitality?

On Friday, we stayed at the Royal Sonesta in Cambridge, MA. The hotel is relatively nice with a great location right on the Charles River overlooking Boston, just a short walk to the Garden / North Station where we watched the Boston Celtics lose to the Orlando Magic (Boston was 2 for 19 from the 3 point line - ouch). When opening the door to our rooms (we had a large suite and a standard twin room that were connected), we were greeted by electric light. Lots and lots of electric light. In fact, there were at least 8 lights on between the two rooms. Each was controlled by a separate switch and had obviously been on for some time awaiting our arrival. We were just stopping by to drop off our bags and then walk to the Celtics game so I quickly made the rounds and made sure to shut off every one before leaving.


After the game we returned to our hotel room shocked to find it equally well lit as when we first arrived. This time I counted and there were definitely 8 separate lights turned on between the two rooms. It seems that in the three hours we were gone, somebody had come into the room just to put chocolates on our pillow and to turn on the lights. It was as if they had each room separately metered and immediately sent somebody up to turn on the lights the second the electricity demand dropped below 100 watts in any room. I called the front desk to ask why our lights were on and was told that it is their policy to do this every time somebody goes into a room, be it to clean up or just to drop off some chocolates. At my request they would not be turning on my lights for the remainder of our stay.


Admittedly, the lights were all compact fluorescents, but this gesture seems disingenuous when the hotel admits keeping lights on at all times is company policy. It also seems at odds with their "Passion for the Environment" signage in the bathroom.