Ventilation challenges in the southeast

We have to deal with ventilation requirements when we work with clients to certify their buildings. Most residential certification programs require that a home or apartment meet the ASHRAE 62.2-2010 whole house ventilation standard. This can be accomplished through exhaust-only, supply-only, or balanced systems. In the humid Southeast, we tend to discourage exhaust-only systems, but some developers and contractors meet the requirement by using a continuous bath vent fan – not the most efficient method, but it is simple. Supply-only systems normally have an outside air intake into the HVAC return plenum with a controller that turns on the HVAC
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From the ground up; utilizing geothermal energy

Geothermal-heat exchange is a great concept, but inefficiency can rapidly change a heat sink into a cash pit. There, post-war America saw the emergence of the futuristic technology that Lord Kelvin, the King of Cold, only dreamed about almost a century before. The fireless furnace ran water through coils within the ground, and sent it through a heat pump to remove burning fossil fuels. “However, while the efficiency of obtaining heat from the earth enhances, it is virtually certain that eventually the heat pump will have the ability to compete successfully with conventional heaters in most localities,” said the report.
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Energy use data and trends

I love those Sankey diagrams showing the energy flows in the US. You can find two versions of them put out by different parts of the federal government. The US Energy Information Administration (US EIA) puts out one type, but it’s not quite as informative as the one that Lawrence Livermore National Laboratory (LLNL) produces. The latest LLNL diagram came out this summer and shows how we used energy in 2012, as you can see below. (To see a larger version along with the 2008-2011 charts, just click the image. It will open in a new tab/window.) US energy flows
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High energy bills and what can be done

She lives in a small, simple house in southern Mississippi. It’s only 1700 square feet. Why then, she wondered, were her summer electricity bills running more than $600? She didn’t have anything that could be a big energy hog, like a swimming pool, and she didn’t do stupid things like leave all the doors and windows open while she ran the air conditioner. What could it be? She called her electric company, one of the co-ops in Mississippi, and they sent someone out to investigate. Utility companies get calls like this all the time, and they’ve learned from experience what
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Green construction woes

Over those many moons I have done some contract writing for the USGBC on the LEED for Homes Version 4 Reference Guide, completed the Georgia energy code required Duct and Envelope Testing on countless new homes, given presentations in Colorado, Baltimore, Greenville, and Atlanta, had three new minisplit HVAC units installed in my house, certified single and multifamily buildings under different green programs, and done some general green consulting for owners and builders. Too little too late It’s this last portion of my work that brings me the most frustration. Too often I am called in to help make projects
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