Tracking electricity on BPA’s electric grid is not as simple as accounting for inventory in a large warehouse, where you can physically track products coming in and out of the building. But a grid modernization project is focused on improving BPA’s ability to do just that. The short-term available transfer capability project automates and increases the accuracy of the process used by BPA to determine how much electricity is moving through a transmission corridor to determine what additional transmission can be sold from today up to 13 months in the future.
Delivering electricity is not as simple as directing electrons from point A to point B. Electricity will travel proportionately across all transmission lines available to it to get from the point of origin, or generation, to the point of delivery (also called load). Calculating how much energy can actually go across those various paths is critical for understanding how much additional ATC can be sold.
“We’ve calculated short-term ATC for a long time at BPA,” said Kevin Johnson, an electrical engineer in Transmission Operations Support. “But the problem has been that many of those inputs to our power calculations, as well as the entry of additional transmission adjustments, into our commercial sales software platform have been very manual.”
As the project progresses, the accuracy of the calculations of short-term ATC will be evaluated to help further refine its performance. Through that refinement, the project will bring a higher degree of certainty in how much electricity travels across individual transmission paths in real-time to better reflect the unique characteristics of BPA’s system. These changes will allow planners and operators to operate the Federal Columbia River Transmission System less conservatively and maximize the use of the system.
“This project should result in having more transmission capacity to sell,” Johnson said. “Better information and data-driven, risk-informed decisions on our modeling assumptions should lead to us being less conservative in general.”
One example of improving the modeling is changing the base case that is built on seasonal conditions – spring, winter and summer – to a monthly model.
As engineers develop monthly cases during this two-year project, those cases are being incorporated into the short-term ATC methodology. The team is also addressing metrics and reviewing actual performance to determine the accuracy of ATC based on the inputs and make adjustments as needed.
The team is also increasing engagement with BPA’s transmission customers.
“Part of our effort is to make the methodology more transparent to customers,” said Margaret Olczak, a public utilities specialist in Transmission’s Operations Support. “One way we accomplish that is aligning all of our documentation so that it is consistent and clear.”
“We’ve made several changes already with short-term ATC, and our customers at the last workshop were happy that we were able to make significant progress.”
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