Economy-wide carbon dioxide emissions in New England fell by 28 to 34% between March and June versus a year earlier, driven by a big cut in transportation because of stay-at-home orders issued in response to the COVID-19 pandemic.

But carbon emissions from the region’s electric generation increased 1.4% in the first half of 2020 because the retirement of Entergy’s 680-MW Pilgrim nuclear plant in Plymouth, Mass., caused an increase in natural gas generation, ISO-NE’s Patricio Silva told the ISO-NE Planning Advisory Committee on Thursday.

The U.S. saw a 7% cut in electric generation in April versus a year earlier and a 16% reduction in emissions. The Energy Information Administration is projecting that U.S. energy-related carbon emissions for 2020 will be 11% lower than in 2019.

The pandemic caused significant reductions in electric demand during the spring, but load has rebounded with the hot, humid weather of July and August, ISO-NE’s Jon Black said.

Black provided the PAC a briefing on Moody’s Analytics’ updated macroeconomic forecast and performance of the peak load forecast model in preparation for the 2021 Capacity, Energy, Loads and Transmission (CELT) forecast.

Because of the pandemic, Moody’s June 2020 forecast predicts real gross state product (RGSP) for the region to be 7% lower in 2021 than projected in its October 2019 forecast used in the 2020 CELT, recovering somewhat to 1.4% lower by 2024. Black said that translated to a baseline summer demand forecast for 2021 that is about 113 MW lower in 2021 and 24 MW lower in 2024.

The baseline assumes that new COVID-19 infections peaked in April and there is no second wave that causes states to shut down again, with a 6% confirmed case fatality rate and a 10% hospitalization rate.

Moody’s said there is a 4% chance that the RGSP will be as much as 14.3% lower in 2021, rebounding to 8.5% lower by 2024. That would result in a 232-MW reduction in summer 2021, with a 147-MW reduction in 2024. It is based on a 12% confirmed case fatality rate and 17.5% hospitalization rate with a much higher than expected incidence of new infections and deaths in late 2020.

ISO-NE plans to use Moody’s October 2020 macroeconomic outlook to develop CELT 2021.

Comments due on Boston Tx Project

ISO-NE will open a 15-day comment window on its selection of the $48.6 million Eversource Energy-National Grid project to reinforce the Boston-area transmission grid in response to the retirement of Mystic Units 8 and 9.

The RTO announced the companies’ Boston Area Optimized Solution (BAOS) as the winner of its first competitive transmission procurement on July 17. (See ISO-NE Chooses Incumbent as Boston RFP Winner.)

ISO-NE’s Andrew Kniska, who briefed the PAC on the project, said the comment period will begin once the RTO posts the draft solutions study report.

The BAOS was the cheapest of 36 projects submitted in response to the RTO’s solicitation, which called for addressing an N-1 115-kV line overload and three N-1-1 345-kV line overloads. It also sought a dynamic reactive device (DRD) to aid in system restoration.

The utilities will install one 11.9-ohm, 345-kV series reactor on each of the two 345-kV Woburn-to-North Cambridge cables at the North Cambridge substation. A normally closed bypass breaker will be installed in parallel with each series reactor and opened only when there is a need to switch in one or both of the reactors.

They also will install a direct transfer trip scheme on the 394 line in response to the contingency causing the 115-kV K 163 line overload and install a +/-167-MVAR static synchronous compensator at the 345-kV Tewksbury substation.

Kniska said the RTO’s steady-state analysis found the BAOS solved the thermal needs and did not introduce any new thermal or voltage violations. The short-circuit analysis found all area circuit breaker duties were within their limits, and the DRD was found to meet the needs for reactive injections.

“The reactors have a bypass breaker to allow operators the flexibility to open and close them … as they see [is needed] for either operational flexibility or maintenance,” Kniska said.

One stakeholder asked about the rules for the operator to determine the need for deploying the breakers. “Are we in an N-1 condition and you open the breaker because you’re afraid of an N-1-1 occurring?”

“I don’t have the details on … how the operators will use them,” Kniska responded. “Obviously, from our needs assessment, this is for N-1-1. If you have the first contingency out, they will need to be in to protect the second contingency.”

Kniska said the proposed plan application study will include a transfer analysis “to determine if there’s any adverse impact on any of the operating conditions, including the interface import capability into Boston.”

Eversource and National Grid told the PAC in June they would reduce their return on equity by 25 basis points if they exceed the $48.6 million cost cap by more than 5%, with additional 25-point reductions for each incremental 5% overrun.

The project is expected to be in service in October 2023.

3 Tx Projects Canceled in Revised SEMA/RI 2029 Needs Assessment

ISO-NE will cancel three transmission projects because of reduced load expectations in the revised Southeast Massachusetts/Rhode Island (SEMA/RI) 2029 Needs Assessment.

The RTO’s Kaushal Kumar said the needs assessment was revised to determine if projects that have not started construction are still needed in light of the decrease in forecasted loads and other changes in study assumptions since the SEMA/RI 2026 Solutions Study.

Of the 15 projects from the SEMA/RI 2026 Solutions Study that have not started construction, 11 were confirmed as still needed and will be retained.

Canceled are:

• Project 1733: Separate the 325/344 double-circuit tower lines, from West Medway to West Walpole (Estimated project cost: $17.9 million; spending to date: $1.1 million).
• Project 1719: Install a 45-MVAR capacitor bank at the Berry Street substation ($5.0 million; $1.5 million).
• Project 1723: Reconductor the L14 and M13 lines from the Bell Rock substation to Bates Tap ($38.7 million; $2.6 million).

A project to replace the 345/115-kV Kent County T3 transformer (Project 1724) also was determined to no longer be needed, but “the decision was made [that] this project will move forward,” Kumar said, because of the age of the current transformer and because $3 million of the $5.9 million cost has already been spent.

The existing transformer, which was installed in 1971, is the last remaining 345-kV transformer of its kind in National Grid’s fleet and has a higher-than-normal potential for failure, Kumar said.

Kumar said short-circuit levels have increased to 40 kA on the 115-kV system at the Kent County station, largely because of two new autotransformers. Similar units have failed in recent years because of short-circuit events outside of the transformer protection scheme, he added.

National Grid had put the project on hold late last year. Its new in-service date is March 2022.

Comments on the revised study will be accepted until Sept. 11.

Eversource Outlines $38M Line Rebuild

Eversource will spend $38 million to replace conductors and wood poles on its 10.3-mile 115-kV line between Harwinton and Watertown, Conn. (Line 1191).

Constructed in 1933 as two parallel 27.6-kV lines, the span was bundled and reconfigured to a single 115-kV line in 1957.

Eversource’s Christopher Soderman said the utility will reconductor the line and replace 96 wood H-frames and one lattice tower with new single-circuit weathering steel monopole structures. Four structures will be removed to optimize the line, Soderman said.

Soderman said the existing 2/0 copper conductor and 3/8-inch Copperweld shield wires are obsolete and prone to failure because of thermal rating degradation and degradation from environmental factors.

He said 2/0 copper conductor is no longer used for transmission, and hardware for it is not readily available, requiring “non-traditional” repair methods.

In addition, about 30% of the existing poles show evidence of woodpecker damage, rot, decay, splits or cracked arms, he said.

The in-service date is the second quarter of 2022.