CARMEL, Ind. — MISO is hesitant to grant a request from Michigan to give dispensations to distributed energy resources from its mandated affected studies that gauge transmission system impacts.

Michigan regulators and utilities’ recent bid to allow DERs to altogether skip out on MISO’s affected system-style studies might be shortsighted, said MISO Senior Manager of Resource Utilization Kyle Trotter.

“Generally, we are supportive of this particular issue; however, we’re not quite sold on an exemption from the whole process,” Trotter said during an Oct. 16 Planning Advisory Committee meeting.

Trotter emphasized the need for appropriate reliability assessments for DER additions. He said MISO cannot ignore DERs’ potential to affect local transmission systems and neighboring systems. Trotter said MISO needs some “touchpoint in place” to maintain visibility of DERs, continue to meet NERC reliability standards and have an idea of which interconnection points on the system are congested for its interconnection queue.

“We need to see what’s happening at those transmission-distribution interface. We need to keep visibility into what’s happening whether those DERs go through the MISO study process or not,” Trotter said.

Trotter also said MISO’s upcoming compliance with FERC Order 2222, which will allow aggregated DERs into the MISO markets, presents another reason to keep tabs on DERs.

“We would like to know about these before they show up and register for the market,” Trotter said.

Last year, MISO decided it would evaluate the need for a review of DERs when they can inject 5 MW of power at the substation level during system peak load and if they can force a 1% change in line loading. TOs screen for the 5 MW injection capability, while the RTO ascertains whether the DERs could influence a 1% line-loading change.

If the DER is shown to impact both reliability criteria, MISO issues a report that triggers its existing facilities study and could lead to network upgrades. TOs pay a $60,000 study deposit to MISO per substation that is required to be studied for DER impacts. MISO refunds any portion it doesn’t use for the studies. (See MISO Creating Means to Gauge Impacts of DER Interconnections.)

In July, Michigan utilities and the Michigan Public Service Commission asked MISO to rethink a study requirement for DERs that might influence the grid. They said MISO’s study process is burdensome, costly and limits efforts to integrate DERs on the grid. (See Michigan Utilities Call for Opt-Out on MISO DER Affected System Studies.)

Some stakeholders said MISO’s DER-affected system studies are redundant considering that MISO’s transmission owners already study DERs’ influence under transmission expansion planning and that MISO is devising a registration process for DERs that want to participate in markets.

ITC’s Ruth Kloecker agreed that MISO’s study process seems duplicative. She also said MISO’s 5 MW threshold seems too severe.

“5 MW of injection? I don’t know how that can seriously impact the transmission system,” Kloecker said.

Erik Hanser, a staffer with the Michigan Public Service Commission, asked if MISO sees a way to cut back study requirements on DERs.

Trotter said MISO would like to continue DER awareness and likely would maintain MISO’s policy of having TOs vet DER additions and notify MISO if an impact study is warranted. He said there’s a possibility DER additions could skip a “full MISO study and associated costs in some instances.”