Net Metering and the Duck Curve

Net metering is a solar policy adopted by many energy providers which allows customers with solar panels to sell their excess energy back to the grid during peak solar generation hours. While this sounds great in concept because it gives incentives to install more solar, it has some issues. The main problem with net metering can be illustrated by a graph known as the “duck curve” because of its resemblance to a duck.

The graph has net load on power plants on the Y axis and hours of the day on the X axis. It can be seen that net load increases significantly during the evening hours of the day. This is because the sun is setting and everyone is getting home from work, decreasing generation and increasing demand. This ramp in demand is difficult for utility companies to keep up with, and can have even more issues when solar adoption becomes more widespread. If solar energy production from households exceeds demand during peak production hours, utility companies can have trouble balancing the electrical frequency of the grid.

Net metering also incentivizes the install of inherently unsustainable solar systems. Fundamentally, solar power generation must be paired with a battery system because it does not output power during sun down hours. Net metering allows households to rely on the grid as a “battery”, when it is not a battery. If everyone tried to use the grid as a battery, there would be reliance on power plants and excess power during the day.

In order to solve the problem of net metering, there has to be more emphasis on installing batteries in unison with solar systems. In order to incentivize this, the price of electricity needs to substantially fluctuate throughout the day in order to reflect supply and demand. This would cause individuals to profit from installing battery systems in their houses and selling electricity at peak demand hours.