June 19, 2009
SOLAR 2009 conference
Last month, I attended the American Solar Energy Society (ASES) national solar conference, SOLAR 2009, in Buffalo, NY. Overall, the mood was very excited and positive. There was a strong feeling of mobilization of the industry to capitalize on the developing mainstream interest and drive the solar industry into the forefront of today's energy solutions. There was a lot of discussion about the national energy situation, the aging electrical distribution system, smart grid developments, and how renewable energy generation fits into this complex system. Solar energy generation at the residential and community levels plays an increasingly important role.
Photovoltaic (PV) energy production is obviously dependent on the time of day and the weather. Because of this inherent variability, solar energy is not well suited for reducing base load power plant use. However, it can do a good job at reducing peak energy demand. This is very important. The base load power plants run continuously to satisfy the baseline needs of the electrical grid. They are best operated at steady state with very little fluctuation. As demand grows during the day, intermediate and peaking power plants are brought online to handle this increased load. The peak occurs in the afternoon and evening in the warmer months. This is when people return home from work and the air conditioning loads are the greatest. The peaking plants are the most expensive to run, so the energy purchased by the utility during these periods costs a lot. Residential, commercial, and utility-scale PV systems can reduce the peak, reducing the operation of these expensive plants and in some cases avoiding the construction of new base or intermediate load power plants.
Beyond peak load reductions, having solar systems on houses and businesses distributed throughout the grid can help with capacity issue on the transmission lines servicing areas far away from power plants. Many of these older transmission lines are reaching their practical limits for transmitting power at times of high load.
Solar thermal systems, providing heat for domestic hot water and sometimes space heating, aren't as visible in the media as PV systems are at this time, but it isn't because they are ineffective or uneconomical. Solar water heating systems work in many more areas than people tend to think. There were several presentations of successful solar thermal deployments in locations that locals consider too cloudy. It is very important to simulate performance and get accurate quotes for installations before jumping to the conclusion that a solar thermal system won't work in a particular location. Installation costs are still a major concern, but there are more and more turnkey systems on the market that aid in quick, simple, and less expensive installations. One study that looked at solar performance, installation costs, and cost savings across New York State found that the performance and economics were very dependent on the local climate and local fuel and installation costs. What makes economic sense in one part of the state doesn't necessarily elsewhere. Good system design requires attention to the microclimate where it is to be located.
There are no really simple answers when it comes to choosing how to address renewable energy systems for houses. Each builder needs to consider, ideally with their solar installer and/or energy professional, all aspects of the construction, performance, local and federal incentives, and economics when choosing what type, configuration, and size of solar system to install. The tools and resources for doing this are continually getting better and more accessible.
For more information, check out the American Solar Energy Society website: http://ases.org/
Posted by Eric Helton at 11:43 AM | Comments (1) | TrackBack
