Options to reduce net load variability in a campus with very high solar penetration

The last decade has seen the increase of solar and wind generation systems which has led to high grid penetration of such technologies. Currently, the issue of grid stability and reliability with increased levels of such non-dispatchable generation is of great fundamental concern. This paper reports on the results of analyzing 15 min monitored data over a whole year from a large university campus with over 50% solar penetration of one of its four sub-stations. Net loads or electric purchases are the differences between the campus electric load and the electricity production of the solar system. These net loads are analyzed both in terms of diurnal "duck curves" and as load duration curves in order to determine the frequency and magnitude of different ramping up and down events experienced during the onpeak and off-peak periods. The extent to which such events can be tempered by installing combined heat and power (CHP) systems is studied, and it is found that increases in levels of net load stability vary non-linearly with size of the installed CHP system. Though the results are specific to this case study, the methodology adopted and some of the results and conclusions reached would be useful to those performing similar evaluations in other parts of the world.