Maine's lunar energy initiatives in 2010 so far.

Tidal energy, or, more properly, "lunar energy", is more reliable than any other renewable energy source. Unlike solar and wind energy extraction, it is not limited by time of day, nor by cloud cover or local wind speeds. There is little chance of the moon changing its orbit or orbital velocity any time soon. 

Just-released Maine DEP emails and other documents on tidal energy in Maine, January - June 2010, obtained via  a Freedom of Access Law request,  detail some of the  the tensions and dynamics between agencies and actors in this new (for Maine) field of tidal energy.

What is the effect of continuous industrial-scale  tidal energy extraction on tidal waterbodies?  For, like other energy extraction tech,  tidal energy extraction devices parasitize megawatts of power  from the local natural energy systems they are operated within. They are persistent "energy sinks" within those greater tidewater systems where they are installed.  

Like any extractive technology, small impacts from small operations. But multiply those small operations, and boost their effectiveness, and unintended collective consequences can happen across a tidal bioregion

Happily half of the investor lemmings who surged toward Maine coastal waters in recent years have abandoned their quests.  A June 2010 report by Maine DEP  (3pg pdf) shows that out of 19 tidal and wave energy development applications given out  by the state, seven had been "surrendered", three withdrawn and one rejected.

The Ocean Renewable Power Company is a survivor; ORPC may start pulling power out of Cobscook Bay this year. Maine Maritime Academy and its TEDEC consortium, are also on the move.  First okayed October 9, 2007, their project will including installing modular TideGen submerged rotors in Cobscook Bay. A  "Breus" rotor  designed by Sergei Breus of Blue Hill is also involved.

The Bagaduce River may give up 15% of its tidal energies to the Marine Maritime Academy-led TEDEC consortium.  was  found "not subject to FERC licensing" on March 23, 2010, freeing it from needing to meet important federal requirements.. On May 5th  MDEP  decided they didn't need a permit so they 'terminated"  the preliminary permit. The Academy plans to install a "Breus" rotor  designed by Sergei Breus of Blue Hill,  Maine

So, what might the effect of  continuous industrial-scale  tidal energy extraction on a tidal waterbody be? 

Water velocity and tide height is different on either side of a tidal energy extractor up to 15% different. Just as air pressure is different on either side of an operating ocean windfarm. Figuring out when and where that energy extraction makes a difference in local weather and local water conditions   needs to happen in this experimental phase of ocean energy development.  

Before contracts are signed, and tons of steel and composites start to assemble.  Because, once the Great Tide Rush is on, and large utilities begin buying up the individual tidal power operators that have snapped up square mile after square mile of Maine coastal waters,  it will be much harder to  modify the technology or correct  its deployment, to minimize what is in effect, "tide pollution".

For example, will they slow down or redirect the critical annual migration of  larval lobsters from downeast waters into Penobscot Bay and points south?   Or, alter the tidal cycle of a particular bay or tidal river enough to delay the arrival or bloom of those even smaller microprey that our larval lobsters and larval cod  must have if they are to survive their first precarious months of existence

Like the environment of any area exploited by an extractive industry, the environment of the locations where  tidal energy withdrawal takes place is/will be changed. Whether the changes are benign or injurious, it is the duty of the state to require those changes be identified and quantified, and evaluated for their impacts, onsite and off short term and over time. Only then are informed decisions possible.

While MMAs Tidal Energy Center is dedicated to  prototyping experimental systems, the goal is to stimulate commercial- or community-scale tidal power extraction in state waters. Unless the state has got some real data to model from, it won't be able to predict whether a proposed large scale tidal system is problematic to critical regional or local  plankton flows or other tide-dependent biological activity.

This will guide the expansion of commercial and community-scale lunar energy extraction.

Norway has belatedly begun doing this with ocean windfarms Its meteorology agency has been intensively studying its nation's ocean windfarms, and discovered that energy withdrawal from the lower atmosphere winds by ocean windfarms is quantifiable and is  significant to climate and to water quality.

We should be equally careful with our tidal energy development.