By Amanda Durish Cook

CARMEL, Ind. — MISO is seeking to more closely harmonize its load forecasting process with the four 15-year future scenarios it creates to support long-term transmission planning, but stakeholders are wary of two ideas being floated by the RTO.

“I think it’s time we move to where the … load forecast is future-dependent,” John Lawhorn, MISO senior director of policy and economic studies, said at a Jan. 17 Planning Advisory Committee meeting.

Lawhorn said that the futures created for the MISO Transmission Expansion Plan could link up with the load forecast in one of two ways: require load-serving entities to supply detailed planning-level data for each of the futures; or use the RTO’s “independent” load forecast as a starting point to create forecasts for each future.

“In both cases, the level of information would be the same; it would include a 20-year forecast, energy efficiency, demand response [and] distributed generation,” Lawhorn said.

“It’s a paradigm shift,” he said. “It’s becoming increasingly evident that a long-term forecast is needed to study the futures,” citing the potential for MISO to swing from summertime peak planning to possible hour-by-hour planning for a future in which smaller distributed generators provide scatterings of energy.

The biggest hitch with the current forecasting approach is that MISO can’t get a clear picture of demand-side management programs, which will be instrumental in forecasting future demand, Lawhorn said.

“This is driving our planning process to areas that we haven’t yet been forced to look at in this level of detail,” he added.

Developed by Purdue University’s State Utility Forecasting Group, MISO’s independent load forecast does not draw on any of the futures, which include “limited,” “continued” and “accelerated” fleet change predictions, as well as a scenario in which distributed generation and emerging technologies gain popularity. The independent forecast also does not account for individual load forecasts produced by MISO’s LSEs, but instead relies only on publicly available information to predict summer and winter peak energy demand for the RTO’s 10 local resource zones along with systemwide peaks.

Unlike the 10-year forecasts produced by LSEs, the Purdue forecast is for informational purposes only — not tied to any official MISO predictions — with an Applied Energy Group study lending the independent load forecast its projections for EE, DR and DG. But the RTO now thinks either the Purdue or LSE forecasts could perform a larger role in transmission planning.

MISO says its pace of fleet evolution “highlights the need to create a new source of load forecasts tailored for long-term economic planning.”

“Our process lacks transparency and it lacks … the detail needed to effectively and efficiently move energy to all areas of the MISO footprint,” Lawhorn said. He also said the 140-plus separate LSE load forecasts currently lack a common set of assumptions.

Two Approaches

If the RTO decides to have LSEs prepare more detailed forecasts, they would have to ready four separate 20-year forecasts, a total of 8,760 hourly load shapes, 20 years’ worth of demand-side management growth predictions, and four iterations of program penetration for EE, DR and DG.

MISO could adopt the LSE-centered approach by the 2021 MTEP at the earliest, Lawhorn said, noting that it would take a minimum of two years to modify the RTO’s member website to accept more detailed information.

Currently, LSEs submit 10-year demand and energy forecasts, extrapolated for another 10 years to develop a 20-year forecast.

“By having a 20-year forecast, you might be outrunning the headlights of state regulators and local planners,” said David Harlan, president of consulting firm Veriquest Group.

“That level of specificity is where the industry is heading,” Lawhorn replied.

MISO’s second load forecasting option involves a third-party consultant like Purdue developing a 20-year demand and energy forecast for each local resource zone by future scenario. Such a system could be in place by MTEP 19.

PAC Chair Cynthia Crane asked whether MISO plans to calibrate a long-term third-party forecast against the shorter forecasts furnished by LSEs if it takes the second route.

“Oh, absolutely,” Lawhorn said.

LSE Ability to Forecast

Stakeholders are divided over how difficult it would be for LSEs to provide more detailed forecast data.

Indianapolis Power and Light’s Lin Franks said there’s no reason MISO couldn’t begin now to use more detailed LSE information for load forecasts.

Lawhorn responded that it’s a “fairly considerable task” to coordinate forecast information from more than 140 LSEs, noting that not all of them are prepared to offer that level of detail. MISO will instead issue a survey to determine the feasibility of producing 20-year forward-looking data, he said.

Customized Energy Solutions’ Ted Kuhn pointed out that forecasts are only worthwhile if MISO develops a process for historically assessing their accuracy. He said the RTO must be able to compare forecasts with actual demand.

Minnesota Public Utilities Commission staff member Hwikwon Ham said he thinks “the independent load forecast is as good as the input used.”

American Electric Power’s Kent Feliks said it’s a “daunting amount of work to require all 140-plus LSEs to provide 20-year forecasts.”

“It seems like an awful lot of resources spent … for little improvement,” he said.

Other LSE representatives at the meeting said creating a load forecast would be a nominal challenge, as they already collect the data needed to prepare forecasts for each MTEP future.

WPPI Energy’s Steve Leovy asked MISO to be more specific about what kind of forecasting information LSEs will be asked to provide. “I’m concerned with what I see, to be blunt, is a half-baked proposal,” he said.

Other stakeholders questioned what came of a 2017 presentation aimed at blending Purdue’s independent load forecasting with LSEs’ 10-year forecasts. (See Bigger Role Seen for Independent Forecast in MISO Tx Plan.)

Madison Gas and Electric’s Megan Wisersky said that LSEs will not be able make an informed choice between the two approaches until they research the costs of preparing more in-depth forecasts.

Lawhorn said MISO is collecting input on the new pair of proposals, and that he would return to the PAC in June to discuss the RTO’s take on the prevailing stakeholder opinion.