May/June 2011

Your Letters

Challenging the status quo

Excellent article (InTech January/February, "Black armbands for APC?"). Challenging the status quo is a good way to promote improvement. I know there are APC installations that fail due to insufficient engineering (inaccurate process models, improper tuning, poorly performing regulatory controls, etc), and APC cannot make up for these deficiencies.

Pat Dixon

Solar incentives

The "Solar power coming of age" article (March/April InTech) indicates the "coming of age" for solar energy but does not seem to indicate what the true economics of the technology are. My understanding is that they are breakeven for most applications with incentives at 15 years or longer with a replacement life of some components already passed. I think the article would be more useful with more specific information regarding why the writer believes the technology has come of age based on cost/benefit rather than that the technology has been around and is somewhat mainstream. Solar energy is mainstream, primarily because of incentives at local and federal levels plus the regulations dictating percentages of renewable energy portfolios.




I appreciate the feedback. Certainly, incentives are a big part of the financial analysis, and if they change, they have a big impact on economics. Energy price increases will also have a big effect. While solar manufactures of serious size are guaranteeing their systems for 20 years, you bring up a good point about the other electrical equipment required that bears some research. The equipment and maintenance costs over time must be considered in an economic analysis. I think solar has advanced as witnessed by an increase in installations and certainly incentives have been a part of this in the U.S. In addition to longer warranties on solar panels, I think an indicator that solar is coming of age is that companies are willing to provide systems to users without capital investment. These companies will install and maintain solar with no investment or cost to the facility owner and guarantee electric prices for 20 years from the system. 

Bill Lydon, InTech, chief editor