Alicen Kandt

Analysis of Web-Based Solar Photovoltaic Mapping Tools

As the demand for renewable energy has grown, so too has the need to quantify the potential for these resources. Understanding the potential for a particular energy source can help inform policy decisions, educate consumers, drive technological development, increase manufacturing capacity, and improve marketing methods. In response to the desire to better understand the potential of clean energy technologies, several approaches have been developed to help inform decisions. One technology-specific example is the use of solar photovoltaic (PV) maps. A solar PV mapping tool visually represents a specific site and calculates PV system size and projected electricity production. This paper identifies the commercially available solar mapping tools and provides a thorough summary of the source data type and resolution, the visualization software program being used, user inputs, calculation methodology and algorithms, map outputs, and development costs for each map.Copyright

Wave Power for U.S. Coast Guard First District Lighthouses

Lighthouses and other navigational aids are situated near tumultuous seas and thus may be good candidates for early applications of wave energy conversion technologies. The U.S. Coast Guard First District is converting lighthouses’ electrical systems to solar power to divest itself of electrical submarine cables and overhead costs associated with cable maintenance. However, in some lighthouses solar conversion is impractical or may compromise historic preservation. Unless alternative energy sources become available for these locations, they will continue to use submarine cables to run on shore power. Lighthouse sites for which shoreline and wave characteristics are suitable would be good candidates for a wave energy demonstration project. This paper describes gravity wave physics and the characteristics of mechanical radiation (growth, propagation, diffraction, and shoaling). A simple expression for energy content of a wave train with a two-parameter Bretschneider spectrum is applied to spectral wave density data collected from 15 buoys to evaluate wave energy resource potential at 31 candidate lighthouse sites in New England. Annual average wave power per meter of wavecrest varied from 3.9 to 21.7 kW/m at the buoys, and from 3.9 to 9.2 kW/m (with an average of 5.0 kW/m) at the lighthouses (buoys with maximum wave power are far out to sea, but still influence the correlation). The performance characteristics of two types of wave energy conversion technologies are used to calculate annual energy delivery by way of example. The paper concludes with a discussion of economics and environmental and permitting issues. It identifies Seguin Island light off a point in Maine and Nauset Beach, Chatham, Nantucket, and Sankaty Head lights (on Nantucket Island and along the outer shore of Cape Cod) as the best sites to begin more detailed evaluations, based on a comparison of wave power and utility rates. Subsequent studies would include demand profile for lighthouses, supply profiles, and resulting storage requirements.Copyright

Remote power systems for sensors on the northern border

The National Renewable Energy Laboratory (NREL) is working with the Department of Homeland Security (DHS) [1] to field sensors that accurately track different types of transportation across the northern border of the U.S.. To do this, the sensors require remote power so that they can be placed in the most advantageous geographical locations, often where no grid power is available. This enables the sensors to detect and track aircraft/vehicles despite natural features (e.g., mountains, ridges, valleys, trees) that often prevent standard methods (e.g., monostatic radar or visual observers) from detecting them. Without grid power, portable power systems were used to provide between 80 and 300 W continuously, even in bitter cold and when buried under feet of snow/ice. NREL provides details about the design, installation, and lessons learned from long-term deployment of a second-generation of novel power systems that used adjustable-angle photovoltaics (PV), lithium ion batteries, and fuel cells that provide power to achieve 100% up-time.

Power systems for remote sensors on the northern border

The National Renewable Energy Laboratory (NREL) is working with DHS to field sensors that accurately track different types of transportation on the U.S. northern border. To do this, the sensors need to be placed in the most advantages geographical locations, often where no power is available. This enables the sensors to detect and track aircraft/vehicles even though natural features (e.g., mountains, ridges, valleys, trees) often prevent standard methods (e.g., monostatic radar or visual observers) from seeing them. Without grid power, intermediate sized portable power systems were used to provide between 80 and 500 W continuously, even in bitter cold and when buried under feet of snow/ice. NREL provides details about the design, installation, and lessons learned from long-term testing of an initial set of novel power systems that used flexible photovoltaics, lithium ion batteries, and fuel cells that provided backup power to achieve over 95% up-time.