by Paul Kando
Coastal Journal contributor

DAMARISCOTTA MILLS — It has been said that nothing would exist without energy. The village of Damariscotta Mills, which straddles the town line between Nobleboro and Newcastle, certainly would not. Luckily, it does, and even has a colorful renewable energy-history. In 1729, water-powered sawmills opened here at the head of the falls between Damariscotta Lake and the tidal headwaters of the Damariscotta River. In 1923, Central Maine Power Co. built a 5 megawatt hydroelectric power plant below the falls. Now owned by Canadians, this plant is still in operation. The sawmills, however, are long gone; only the mill pond and the village name remain to evoke their memory. Because the sawmills blocked the alewives’ way to their natal waters in the lake, legislative concerns were expressed as early as 1741, and a call was issued for reopening a fish passage. The “New Stream” fish ladder was finished in 1807. Built of dry-laid field stones, it has severely deteriorated over two centuries of winter-frosts, spring thaws, floods, and occasional hurricanes. With whole sections in ruin, it became near-impossible for the fish to reach the lake yet again. 

After years of stop-gap repairs, a thorough rebuilding project was finally launched in 2007 with the reconstruction of a crumbling section of wall 40 feet long and 12 feet high. Since then, restoration has proceeded in annual phases, each to be completed between the end of one year’s alewife run and the beginning of the next. Timely completion of each phase is a must, as the ladder must be open for both the upstream passage of spawning alewives and the downstream run of their young. Heavy machinery cannot easily access the middle section of the ladder, which includes sections most in need of repair. This makes reconstruction of crumbling pools and stone walls there especially challenging.

by Paul Kando
Coastal Journal contributor

If you have money stuck in some CD or investments that barely keep up with inflation, consider investing in upgrading the energy efficiency of your home for a far better return. A case in point is this 1965 vintage 2,119 square-foot cape in Northport. At the time of a fall 2011 energy audit, the cedar-shingled house was surrounded by bushes, planted by an earlier generation, virtually touching the building, and the family burned 1,100 to 1,200 gallons of oil annually for heating and hot water, maintaining an average indoor temperature of only 58 to 62  degrees Fahrenheit. Calculated energy use was 6.56 kWh per Heating Degree Day, with a carbon footprint 16.7 tons of carbon dioxide, about 15.7 pounds per square foot of heated floor space. 

The home’s two-by-four framed, fiberglass insulated walls had a total thickness of 5.5 inches and a total R (insulation) value of 14, the two-by-six framed, 7.5-inch-thick, asphalt shingled roof had an R value of 21, and the 8-inch thick poured concrete basement floor and walls an R value of 1.6. The blower door measured 5.05 air changes per hour at 50 Pascals pressure (ACH), which corresponds to a complete natural air change every 2.5 hours. The combined area of all the air-leakage holes and gaps throughout the heated envelope came to 0.9 square feet open to the elements 24/7. Heat losses totaled 35,008 kWh/yr, of which 36.9 percent were lost through the walls, 21.9 percent through the basement, 18.5 percent through windows and doors, 16.0 percent through air leakage, and 5.4 percent through the roof. The remaining losses were due to miscellaneous causes, such as uninsulated pipes in the basement. 

One of a pair of through-the-wall heat recovery ventilation units, showing, from left to right, the shielded interior air inlet/outlet, the reversible, remote-controlled fan, the interior wall plate, the ceramic heat storage unit, the wall cylinder into which everything fits, and the screened exterior inlet/outlet. (Picture courtesy lüftungshop.de, Berlin)by Will Gottlieb
Coastal Journal staff

According to energy audit data, 30 to 60 percent of most Maine homes’ heating energy is lost due to air leaks through holes and gaps in the building envelope. New houses must be built to a higher tightness standard and existing ones must be air sealed. The trouble is that, as building efficiency is improved and buildings become more airtight, they can also become poorly ventilated. Insufficient fresh air can lead to stuffiness, odor buildup, and unhealthy air quality. Lack of supply air for combustion appliances can cause incomplete burning, back-drafting and the introduction of dangerous exhaust gases into the living space. Another major, but often overlooked problem in tight houses is excessive moisture buildup which can lead to unhealthy conditions, mold, and mildew. Condensing moisture can also damage the building structure. Therefore, when a professional energy audit report recommends ways to tighten a leaky house, it must also indicate the safe limit beyond which tightening should not proceed without introducing additional ventilation.

Simply opening windows provides ventilation, however it also causes loss of heat and humidity in winter and excessive gains of same in the summer. This is wasteful and costly. It takes energy for the building’s heating and cooling systems to compensate. Exhaust fans remove stale air, but they rely on a leaky envelope for replacement air. Thus they cannot be relied on for long term ventilation in a tight house.