The hotels microturbines are an example of CHP – combined heat and power.  They use natural gas to power the microturbines that generate electricity.  The waste heat from the microturbines is then used to heat water for use in the hotel.

Marvin Dixon, director of engineering for the hotel, says the $1 million dollar project will pay for itself within 4 years.

Thomas E. Knudsen, president of Philadelphia Gas Works, says the microturbine is 85% efficient.  This compares to about 33% efficiency for the thermal losses of the typical electric generating plant and transmission lines.  Traditional power plants do not recover the waste heat because the plants are often far away from population centers so there is little demand for the waste heat.

In addition to being an efficient system that reduces their carbon footprint, the microturbines have additional advantages:

·      The microturbines give the Four Seasons a backup system in the case of an electric blackout.

·      The microturbines gives them flexibility to make business decisions and choose to buy electricity directly from PECO or purchase natural gas.  In theory, the Four Seasons could also sell the electricity from the microturbines to PECO.

·      Good publicity - Adds to their sustainability credibility along with a rooftop vegetable garden, food scrap composting, and eco-friendly key cards.

·      Microturbine technology is another example of distributed power generation similar to putting solar cells on your roof. Power that is generated locally does not need to be transmitted through the transmission and distribution lines. This is beneficial for our overall electric grid because it reduces the load on the grid.  Since people do not like seeing power lines in their backyards it is hard to find new corridors for power lines.  It can be especially difficult in crowded urban settings like a downtown business district.

So why do businesses like Four Seasons or WalMart invest in sustainable practices?  They do it because it saves them money in the long run and gives them good publicity.  It is a good thing that sustainability is financially rewarding.  To have a significant impact on green house gas emissions, large percentages of society will need to take action.  To get this large response there needs to be a financial benefit.