Monday, January 26, 2009
Wednesday, January 14, 2009
Thursday, January 8, 2009
"Winter solstice is now behind us, so the days are getting longer again. Yet, your facility seems drearier. Being the sharp electrical troubleshooter that you are, you grab a light meter and take some measurements.
When you review your findings against the lighting plan, your suspicions are confirmed. Light levels really have dropped. In some places where the plan shows 45 footcandles, you measured only 25. In an inspection area that requires 90 footcandles, you measured 70. How can you figure out what’s going on?
A drop in light output is hard to isolate in time, because it tends to creep up on us. As light output diminishes a little each day, we adjust to the new normal. That makes troubleshooting more difficult, but not impossible. Light output diminishes as lamps near end of life (the output curve varies by lamp type). So, maybe it’s just be time for relamping. However, there are probably other factors to correct. Things to check include:
Light output diminishes as lamps near end of life (the output curve varies by lamp type). So, maybe it’s just be time for relamping. However, there are probably other factors to correct. Things to check include:
NextEra is the largest producer of wind and solar energy in North America. The company currently has more than 6,300 megawatts of wind generation in operation, or enough to power more than 1.5 million average homes. It also is the largest generator of solar thermal power in the world. NextEra co-owns and operates seven solar plants in California’s Mojave Desert, which collectively form the world’s largest solar site. In all, the company operates 310 megawatts of solar power.
As I lived in the Bay Area during the energy debacle in 2000, I have watched this initiative with great interest. California leads the nation in subsidizing rooftop solar. Most of these systems are grid-tie systems which don't require storage batteries. They use grid-tie inverters to feed the grid such as made by Xantrex. Even so, this can be quite an investment with a long (10-15 year) payback. Looks like the subsidies along with new federal tax credits are driving adoption in California.
The closest thing we have in TN is Green Power Switch. Here as a residential you can buy green power from TVA or one of its distributors. Green generation is at the utility level with this plan.
Wednesday, January 7, 2009
FUUN Sanctuary / January 21
Join producer Jeff Barrie as he screens and discusses his award-winning film Kilowatt Hours: A Plan to Re-Energize America. The film suggests connections between an average homeowner’s electrical energy use and adverse health and environmental impacts, including mountaintop removal coal mining, global warming, and asthma. Kilowatt Ours shows the actions that homeowners, businesses, and communities can take reduce their demand for energy. Get more information at www.kilowatthours.org
First Unitarian Universalist Church
1808 Woodmont Blvd. Nashville, TN 37215
Phone: 383-5760 Fax: 383-5785