DC monitoring raises the bar for solar power plants
Keith Davidson is senior electrical engineer with Suntech Power Holdings, which produces solar panels.
Our electric grid is changing as solar photovoltaic (PV) systems increase both in size and market penetration. As solar power plants achieve larger scale, the operating parameters of direct current (DC) systems become more critical. Stakeholders at all levels, from financiers to engineers, designers, developers, salespeople and end customers, stand to benefit from improved DC monitoring technology.
An incomplete understanding of the benefits that these systems present, coupled with their added costs, can prevent adoption of DC monitoring technology. But as the latest design methodologies and PV technologies evolve, DC monitoring systems will help PV systems produce a return on investment for their owners—and will allow the industry to rely increasingly on clean solar energy for decades to come.
String vs. Module Monitoring
DC monitoring can be implemented in many different forms and flavors, and all topologies have potential benefits and drawbacks. These systems monitor DC performance by measuring and recording DC voltages and currents at specified intervals, which can then be analyzed mathematically to correct for environmental operating conditions and calculate other parameters such as DC energy generated.