Utility scale solar farms range in power output from tens of MW to many hundreds of MW and consequently cover areas ranging from 1 hectare to 1500 hectares (or more). Such installations are made up of building blocks repeated many thousands of times. As any additional cost is multiplied many thousands of times there is a real need to engineer a system that is fit for purpose and cost justified. While the initial capital cost is clearly a primary driver, ongoing robustness is critical to maintaining optimal power output with minimal ongoing replacement and maintenance requirements.
Any solar farm is likely to be struck by lightning multiple times over its lifetime and in some locations many times each year. Therefore, it is important that the lightning protection design and implementation of any mitigation measures manage the threat in a cost effective manner.
This paper has several aims, namely to:
โข Discuss the key requirements the lightning protection design a site,
โข Examine the applicability of the risk assessment process contained in national and international standards.
โข Propose alternative calculations that may be used to extend the current risk assessment methods to include the large, interconnected nature of utility scale solar farms.
โข Discuss a range of mitigation measures that are available to a designer to mitigate both direct and indirect strikes.
โข Present case studies to illustrate the range of responses that may be applied.