If U.S. companies are to realize their sustainability aspirations, which include an ambitious renewable energy purchasing target of 60 GW by 2025, they must engage in transmission planning across the country, according to a new report by the Wind Solar Alliance.

"Companies buying affordable clean energy today are benefiting from yesterday's transmission plans," John Kostyack, executive director of the newly created Wind Solar Alliance, said in a news release. "To meet their sustainability targets for the next decade, and to make low-cost renewable power accessible for themselves and other customers, they need to join efforts to jump-start a new era of transmission planning."

Building on a report issued in January that found U.S. transmission planners do not adequately consider companies' appetites for renewables, the group's latest research, released Oct. 14, provides additional detail about how corporate buyers of renewable energy can shape grid expansion projects. It also cites examples of recent transmission lines that have unlocked some the country's prime wind and solar resources.

Walmart Inc., which has committed to covering its global power demand with renewable energy, is already trying to address the problem by recently joining the Southwest Power Pool regional transmission organization. Also, Microsoft Corp. is a member of the PJM Interconnection grid operator, in the end-use customer sector. In addition to participating in RTOs, companies should explore collaborations with utilities and trade groups on expanding the grid to access stranded renewable energy resources, according to the report.

The need for companies to have a voice in transmission planning comes amid record U.S. corporate renewable energy purchases in 2018, the report found. Through August, companies ranging from Silicon Valley tech giants like Alphabet Inc.'s Google LLC, Apple Inc. and Facebook Inc. to telecoms AT&T Inc. and T-Mobile US Inc., and a host of smaller businesses had contracted for nearly 4,000 MW from utility-scale wind and solar projects. Companies in the Renewable Energy Buyers Alliance, or REBA, have procured 13,100 MW since 2013 as part of a 60,000 MW target by 2025.

To meet that goal, corporations will need to purchase an average of roughly 6,500 MW per year. All of that "is dependent on new renewable energy projects having access to transmission," said the report, which the Wind Solar Alliance is presenting Oct. 15 at a REBA summit in Oakland, Calif.

"Transmission planning entities in many of the regions with the best wind and solar resources are not holistically considering the significant, near-term renewable energy goals set by corporate consumers," it concluded. "And like all governance structures, transmission planning only works for those that participate."