The Storage and Delivery of Wind Energy

One of the things I have always struggled to understand is the role of storage in integrating remote wind resources. We know that developing some of the nation’s best wind resources will require new transmission. But there are many questions about how much storage might help integrate this wind, and where to put the storage – at the wind site or closer to the load? Locating storage on the wind-side of the transmission line can increase the transmission utilization, reducing the cost of transmission per unit of delivered wind. But putting storage closer to load often allows more effective utilization of storage resources. Analyzing this trade off is difficult, as we (ideally) must do a full grid simulation, including storage dispatch, power flow, etc. Recently, my colleagues Jennie Jorgenson and Trieu Mai and I published a paper that looks at this issue at some detail in the Western U.S. In short, we generally find that transmission is generally more effective than storage from the sole perspective of wind integration. That is largely due to the fact that storage is generally more cost effective when it can be deployed with 4 hours or less of capacity. To really benefit wind, more than 4 hours of capacity are typically needed. But we also found some interesting synergies, as the benefits of deploying transmission and storage together were greater than the sum of the individual benefits when deployed alone. As storage costs continue to decrease, these benefits will increase, and we will keep watching for lower cost, longer-duration storage technologies that could help us tap some of the country’s best wind resources.