Integration: Solar project grid integration

Most solar projects require transporting energy from the source to the consumer. Existing transmission and distribution assets may need upgrades to handle the change in load. Centralised solar farms require special considerations for integrating with the grid. As mentioned in the planning phase, the development of new transmission infrastructure can be challenging for political and economic reasons. Using or upgrading existing transmission infrastructure is often the most prudent option to connect solar energy production sites to end-users, though the locations of potential solar sites and consumers may require advanced geospatial analytics to determine how to maximise use of existing infrastructure.

Further complicating grid integration is the variability of solar energy output, which can create higher or lower energy loads than the grid is designed to handle. To account for this, utility-scale solar may use battery storage on-site to help manage energy flow onto the grid.

Distributed systems may or may not be connected to the distribution network. There are several ways that PV owners can benefit from grid connectivity:

• Selling excess energy back to the grid - In some locations, utility companies credit the electricity back to the grid at a rate close to retail price; however, in some other locations, the selling-back-to-the-grid rate may not be attractive.

• Selling power purchase agreements (PPAs) to counterparties (e.g., EV charging operators) - In states with less favorable net metering policies or where counterparties are willing to buy power at a higher rate than the net metering rate, it may be possible to get PPA revenue from selling solar power to counterparties.

• Adding battery storage to consume - DG owner can store excess electricity to use off-peak, or take advantage of arbitrage (export when remuneration is high, import when it’s low). This can be valuable when the levelized cost of storage (LCOS) is comparable/better than the electricity price or when sustainability objectives need to be achieved.