A Vermont utility and a Vermont telecommunications company are partnering to leverage a new fourth-generation long-term evolution (4G LTE) network that will deliver wireless broadband services throughout Vermont and meet the needs of utility smart grid applications for ubiquitous, service-level-based backhaul services.

Green Mountain Power (GMP) is an investor-owned utility serving about 72% of all electric customers in Vermont, a rural state with bucolic hills, beautiful farms in the valleys, charming small towns and a tourist industry that benefits year-round from a variety of seasonal sports and outdoor activities. The winters are cold and snowy, and the Green Mountains and Taconic Mountains bisect the state north to south. With about 625,000 residents and 330,000 electric revenue meters, the state is lightly populated.

These same dynamics, which make Vermont an attractive place to live and vacation, make it a difficult place to develop telecommunications infrastructure. Vermont’s regulatory structure includes a quasi-judicial body called the Public Service Board (PSB) as well as a Department of Public Service (DPS) that represents the public interest and reports to the governor.

A Statewide Collaboration

GMP’s smart grid program began in early 2008 with close collaboration among Vermont utilities, regulators, customers and other stakeholders to develop a shared understanding of smart grid facts and benefits. This collaboration took the form of a docket opened by the PSB. Initially, a series of workshops defined smart grid, developed a shared understanding of the technologies, identified quantifiable benefits, established minimum requirements and optional characteristics, and defined ground rules for rate recovery.

Ultimately, this collaborative group successfully secured a US$69 million federal smart grid investment grant supporting $138 million in projects to implement smart grid infrastructure and programs throughout the state.

Voltage sensor for volt/VAR optimization uses CalAmp Fusion modem

The Backhaul Dilemma

Smart grid requires that commands and data flow easily among smart devices throughout the electric system. The communications backbone that carries this flow is commonly called backhaul. The federal grant made the deployment of smart grid technologies a foregone conclusion for much of Vermont. But the utilities and policymakers faced another challenge with no clear solution: What communications path(s) could provide the backhaul for the smart grid? Even in the most optimistic models, cellular data networks covered less than 70% of the state’s geography, and wired broadband alternatives did not fill the gap.

Keys to the statewide communications development.

In 2007, then-governor of Vermont Jim Douglas had declared the audacious goal of making broadband and cellular service available to all Vermonters by 2012. But in 2008, there still was no clear way to achieve this goal. History shows that, left to its own devices, a utility will build infrastructure owned and controlled directly by the utility in the interest of its operations, customer service and other priorities. The initial plan to achieve smart grid backhaul in Vermont was consistent with this tradition.

The initial plan called for enhancing the utility’s existing microwave networks, leveraging a privately licensed spectrum to achieve homogenous, secure, high-availability backhaul. This would have been a network of which any engineer would have been proud. It also was completely inconsistent with the policy framework that was developing in Vermont.

When the collaborative discussion on smart grid focused on backhaul communications for utility field devices, the paucity of telecommunications options was recognized as a big challenge. At the same time, it was clear the governor’s office and the DPS would not support utility investment in telecommunications infrastructure that did not support the state’s broadband and cellular goals.

In a memorable moment of the smart grid collaboration, the commissioner of the DPS banged on the table and insisted, “… every dollar spent on the smart grid must be leveraged to the greatest benefit of Vermonters!”

From this perspective, it was only natural to see the utilities and their now-funded smart grid projects as an opportunity to kill two birds with one stone for the state. The utilities were going to have to build communications infrastructure to enable a smart grid. So, why not build it in ways that also advanced public broadband access?