Gov. Mills recently announced the creation of the Maine Offshore Wind Initiative, which aims to develop renewable energy in the Gulf of Maine. The program focuses on job creation, port infrastructure, and the supply chain that this new industry will require. Governor Mills also simultaneously approved Aqua Ventus, the first floating wind power demonstration project in the U.S.

However, as Maine has discovered since 2008, planning energy projects is the easy part. The difficult part is building transmission infrastructure and reshaping the state’s energy system to deliver new renewable energy to customers in a cost-effective way. Maine’s onshore wind efforts over the last decade provide a cautionary tale as officials look to the ocean for a fresh renewable energy source.

In 2008, Maine attempted to create an onshore wind industry almost from scratch. The state aimed to install 2,000 megawatts of onshore wind by 2015, from the starting point of a single 42MW wind farm. Over a decade later, Maine has 923MW  of onshore wind – less than half of the 2015 goal.

And only a small amount – 22.8 MW – has been built since 2016. What happened? In part, the contentious debate around wind turbines and Gov. Paul LePage’s damaging moratorium on wind projects played a role. But there is a deeper story about how numerous wind projects were blocked, separate from Gov. LePage’s temporary policy. The largest impediment to the development of wind in Maine has been the lack of an adequate transmission system.

At least five large wind projects were cancelled because transmission constraints prevented their electricity from reaching customers. Combined, these projects would have created an estimated 2,000 jobs and 2034MW of clean energy in northern and western Maine while providing over $44.7 million in taxes and land-lease payments each year. Over 25 years, that would have added up to $1.1 billion in financial benefits for Maine communities.

Transmission bottlenecks weren’t the only thing that prevented these five projects, but they played a fundamental role. The central problem was one of geography: Maine’s largest wind resources are located the north, while the state’s only long-distance high voltage transmission lines are located to the south and east. Even this existing infrastructure has been plagued by congestion as power moves from north to south. In fact, Aroostook County – the location of three of the cancelled wind projects – has no connection to the U.S. grid at all, but instead is connected to the power system of New Brunswick, Canada. This dynamic mirrors Maine’s offshore wind resources, which will require new infrastructure and systematic planning to connect with the onshore grid.

After Maine set ambitious wind energy goals in 2008, wind farm developers submitted a raft of project proposals. They found a power system unable to support their new generation, and only a handful of planned projects ever took place. Like any infrastructure project, new transmission brings difficult cost and environmental choices that require extensive cooperation and joint planning. But transmission also serves as an enabler, creating jobs, investment, and clean energy opportunities.

The five stalled onshore projects – King Pine, County Line, Somerset Wind, Moose-Alder, and Number Nine – each required some degree of new transmission infrastructure. Multiple proposals were put forward to accomplish this, with each rejected or delayed at various stages of development. The Maine Power Reliability Program, a $1.4 billion construction project completed between 2010 and 2015, improved parts of Maine’s transmission infrastructure but did not consider the needs of new onshore wind projects or lay the groundwork for future upgrades.

Siting new transmission can be a challenge, which only makes it more important for the relevant stakeholders – developers, state and local officials, utilities, and transmission organizations – to develop a cohesive and long-term plan. This didn’t happen, and with only two small land-based wind projects under development it appears that Maine’s promising onshore wind industry missed its window of opportunity.

With her recent announcement, Gov. Mills has cast the spotlight towards offshore wind. Maine has an estimated 156GW of ocean wind energy potential – over 30 times greater than the state’s current electricity capacity of 4.9GW.  Seizing this opportunity will require collaboration and systematic planning for enablers like transmission. The state’s onshore wind industry was thwarted by limited transmission, but Maine is fortunate to get a second chance at building a new clean energy industry. This time around, Governor Mills, her administration, and regional entities like ISO-NE will need to combine their vision of offshore wind energy with a well-planned transmission system that maximizes the ocean’s clean energy potential.