peakbagger
In Rembrance , July 2024
"Brown Hydro" is generally referring to a hydroelectric power plant with ponded storage which releases water on a cyclical basis varying the water level of the pond as needed. In the US ponded storage is subject to environmental rules that limit variations in the storage level to reduce the impact to wildlife and erosion issues. There was a large ponded storage project in NW maine proposed 30 years ago, Dickey Lincoln, that went even further by pumping water out of lower impoundment into a higher impoundment at night, then emptying the upper one during the day. Maine has quite a few ponded storage lakes including, Azicohos, Flagstaff, Gulf Island Pond and numerous lakes around Mt Katahdin. NH has Lake Umbagog and Moore dam.
Run of the river plants, ike most of those along the Connecticut and the Androscoggin, have no significant upstream storage and generate power 24 hours per day with minimal manipulation of the water level. Obviously they do have impact as obstacles to fish that swim upstream but this is considered less impact that ponded storage. One of the major obstacles to restoring the Androscoggin River is attributed to the Gulf Island Pond storage pond north of Lewiston as years of high BOD sediments that would have been flushed to the sea long ago are trapped behind the dam leading to the need to inject liquid oxygen it the river to prevent fish kills in warm weather.
There are all sorts of environmental ills attributed to ponded storage dams. Generally its hard on the types of wildlife that existing prior to the flooding of the area, it introduces a large amount of erosion due to the varying water levels, it introduces a lot of methane (which has a high global warming potential) into air from rotting vegetation that is flooded in fairly shallow areas. Obviously whitewater paddlers are also not a fan of dams as they back up the rivers for miles and flood water falls. A free running river has a far better oxygen uptake than a flat lake, in general the water quality downstream of a dam will be of lower quality than prior to the constrcution of the dam. Large impoundments also remove large blocks of old growth boreal forest which at a minimum is a carbon sink.
VT and Mass both banned "brown hydro" as a renewable for years and I beleive the EU has significant limits on what can be claimed as renewable, Mass still has the rules in effect but VT changed the rules last year as a means of acquiring a new source of power to offset the expected closure of VT Yankee and to stave off new fossil fueled generation.
As usual its the regions decision on the relative gains and losses of hydro versus fossil generation. For new England, most of the power generation is natural gas combined cycle plants currently with some nukes and some grandfathered coal plants. As the need for power increases, the current decision for new power is natural gas or hydro. A combined cycle natural gas plant has less footprint and are a lot quicker to build, but they emit CO2, big hydro has a much bigger footprint and local impact but doesnt emit as much CO2.
Run of the river plants, ike most of those along the Connecticut and the Androscoggin, have no significant upstream storage and generate power 24 hours per day with minimal manipulation of the water level. Obviously they do have impact as obstacles to fish that swim upstream but this is considered less impact that ponded storage. One of the major obstacles to restoring the Androscoggin River is attributed to the Gulf Island Pond storage pond north of Lewiston as years of high BOD sediments that would have been flushed to the sea long ago are trapped behind the dam leading to the need to inject liquid oxygen it the river to prevent fish kills in warm weather.
There are all sorts of environmental ills attributed to ponded storage dams. Generally its hard on the types of wildlife that existing prior to the flooding of the area, it introduces a large amount of erosion due to the varying water levels, it introduces a lot of methane (which has a high global warming potential) into air from rotting vegetation that is flooded in fairly shallow areas. Obviously whitewater paddlers are also not a fan of dams as they back up the rivers for miles and flood water falls. A free running river has a far better oxygen uptake than a flat lake, in general the water quality downstream of a dam will be of lower quality than prior to the constrcution of the dam. Large impoundments also remove large blocks of old growth boreal forest which at a minimum is a carbon sink.
VT and Mass both banned "brown hydro" as a renewable for years and I beleive the EU has significant limits on what can be claimed as renewable, Mass still has the rules in effect but VT changed the rules last year as a means of acquiring a new source of power to offset the expected closure of VT Yankee and to stave off new fossil fueled generation.
As usual its the regions decision on the relative gains and losses of hydro versus fossil generation. For new England, most of the power generation is natural gas combined cycle plants currently with some nukes and some grandfathered coal plants. As the need for power increases, the current decision for new power is natural gas or hydro. A combined cycle natural gas plant has less footprint and are a lot quicker to build, but they emit CO2, big hydro has a much bigger footprint and local impact but doesnt emit as much CO2.
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