Matinicus Island energy options

Residents of remote islands often face energy costs that are higher than those on the mainland.  This can be for many reasons, most of which stem from islands' relatively small populations and remote locations.

Islands far enough offshore are often not connected to the mainland electric grid via submarine cables.  If the island is to have its own electric grid, it must develop both generation and distribution wires.  Some island communities are considering renewable energy resources like wind and solar, but for the most part diesel has fueled the bulk of electric generation on remote islands.  Diesel can be expensive on the mainland, and is even more expensive when it needs to be shipped out to the island for consumption.

The Maine island of Matinicus fits this model.  Located over 20 miles offshore, the 740-acre island is home to about 20 year-round residents and about 200 summer residents.  Since 1965, the Matinicus Plantation Electric Company has provided electric utility service to islanders.  The Matinicus utility is consumer-owned, meaning it is owned wholly by its consumers (as opposed to outside investors).  Electric generation is provided by a set of diesel units: two rated at 45 kW and a third rated at 65 kW.  The utility also maintains a 150 kW backup generator for emergencies.  The company does not serve the nearby island of Criehaven, which lacks a centralized electric utility system.

How do the circumstances of Matinicus Island affect energy costs?  In 2010, the Matinicus utility sold 225,000 kWh of electricity at an average rate of 65.2 cents per kWh, or about 4 times the average price residential customers pay on the mainland.  Producing this power required burning a fair amount of diesel - about 40,000 gallons per year.  Many islanders pay about $200 per month for electricity.

The desire to cut costs and enhance the local environment have led to several proposals to switch Matinicus to renewable resources in recent decades.  Some commenters have suggested Matinicus could pursue an island-based wind project as Vinalhaven did, while others view the site as inappropriate.  Others have suggested floating offshore wind could be a match for Matinicus; next summer's test installation of a floating offshore wind turbine off Monhegan could help us understand the impacts of such a project near Matinicus.  Other renewable ocean resources, like tidal energy, could one day play a role in the island's energy portfolio.  For any such project to succeed, it will have to be both cost-effective and palatable to island residents.  Until then, residents and visitors alike can look to the island's diesel generators as the primary source of electricity.