Historically, interchange flows between California ISO (CAISO) and the Nevada Power Company (NEVP) have been at low levels, with an average of 81 MW/h going from CAISO to NEVP from January 2017 to August 2020. However, in August 2020, NEVP started sending an average of 900 MW/h to CAISO, creating a new dynamic. Today’s energy market insight will explore this shift, and the resulting change in emissions attributed to generation used to meet CAISO load.
In their 2013-2014 Regional Transmission Plan, CAISO saw the potential need for a transmission line between two substations in Clark County, NV: NEVP’s Harry Allen substation and CAISO’s Eldorado substation. This 60-mile, 500 kV transmission line, known as DesertLink, came into service in August 2020, creating the transmission capability for the interchange dynamics to shift. However, CAISO’s load, generation, and net interchange all stayed consistent before and after the transmission line came into service. The new transmission line had a significant indirect impact on the interchange between CAISO and the Los Angeles Department of Water and Power (LADWP), with LADWP seeing their exports to CAISO drop since the transmission line came into service.
As a result of an increase in imports from NEVP and a decrease from LADWP, the emissions that can be attributed to generation used to serve CAISO load has dropped. Since NEVP has 809
MW of coal capacity and 1620 MW of solar capacity compared to LADWP having 1640 MW of coal capacity and 873 MW of solar capacity, imports from NEVP likely come from cleaner sources of generation, particularly given the renewables build out in the rest of the western interconnect. Furthermore, NEVP has 7828 MW of natural gas capacity while LADWP has 4863 MW of natural gas capacity, meaning that when the solar panels are not producing energy, NEVP is still producing cleaner energy due to having more of a reliance on natural gas and less of a reliance on coal. All these capacity differences led to NEVP producing less MT of CO2 per MW generated than LADWP.
While DesertLink provides CAISO with cleaner power from NEVP, the transmission line also provides CAISO more access to the renewable buildout in the region surrounding Nevada, as power can flow through NEVP. Since January-2014, the capacity of renewables in the western interconnect, excluding California, Washington, and Oregon, has increased by 14 GW, with much more in the queue. This increase accounts for 15 percent of the 93.4 GW of capacity currently operational in this region.
Furthermore, this region has 17.5 GW of renewable capacity that BTU has graded as lower risk over the next five years and 39.3 GW of renewable capacity early in the planning process. By further increasing transmission capabilities between themselves and nearby balancing authorities, CAISO can gain more access to the clean energy being built out.
To see more about where renewables capacity is being built out, along with access to BTU Analytics’ proprietary grading system for the renewables build out, check out the BTU Power View.