Examples

The plot above shows \(D\) the strength of the duck curve between Jan20-Dec23 using ISONE RT demand data between the hours beginning 7 and 19. As expected, we see the points to exhibit a downward sloping trend year over year reflecting the solar build out in the region over this period.

📝 Note The data above is for RT demand not load. Over time, as more and more batteries are added to the system and charge during the mid-day dip in load, it will lead to an increase in \(D\). That's why we recommend calculating \(D\) using the RT load not RT demand data.

As mentioned before, we are now in position to compare the strength of solar penetration between different geographical regions. Of course, local weather conditions and customer mix will be different between regions, but over time a summary static on \(D\) will reveal existing differences. For example, the plot below compares the RT demand in Maine and NH over the Mar23-Apr23 period. As you can see, Maine values tend to be lower on most days. This is mainly due to the fact that Maine has put a very strong community solar program in place which has incentivized solar development in the state.