Change, Change, Change!

          If you extract a lump of fossil fuel from the earth and assign to it 100 units of potential energy, run it through a typical utility, make steam, generate electricity, and run it out the grid to the meter on your home there are only 3-5 units of power left! Production waste, generation losses, switching, line loss and transformers eat up the energy. Now look at our 200,000,000 + existing home inventory and add the typical energy wasted from duct loss, infiltration and old HVAC systems (often more than 25 - 40%) and the waste factor is disgusting.
            The change we have to embrace is efficient conservation and distributed renewable energy. Homes that achieve net zero energy use and create their own juice remove the distribution losses for residential homes and negate the need for more huge, wasteful centralized utilities. DOE considers residential energy use unsustainable and climbing. We have no energy policy and the 2012 IECC Code is being slammed as unfeasible economically! Where is the common sense in all of this? Our grid is failing, we have working knowledge and experience worldwide for distributed renewable energy and yet we submit to the status quo.
            We have the tools, technology and workforce to retrofit all of our existing home to near-net zero energy use. This idea is not new, nor is it particularly controversial unless you are in senior management at a utility. There have been several home energy retrofit programs floated though congress over the last decade and they all disappear into congressional fog-land. TIME TO ACT!
             Most of our alternative energy leaders are in agreement that this is crunch time, our opportunity to get it right. If we could turn the key on net zero residential home energy use today the inertia of climate change will last 20 years. This is the time to get our act together. 2050 is my target for net zero residential energy consumption, I'll be breathing my last breaths by then and I would like to enjoy them.......

Insulation

Local USGBC meeting in East TN we were happy to listen to Jeff Christian speak on the insulation WARS. Basically we learned that thermal shorts created by studs are the biggest criminals in energy loss, metal is the worst! The solution is a continuous exterior insulation, best is foam board. Insulation should be continuous and contiguous.

Heat Pumps

              For the past few weeks I have been testing homes that are recent participants in TVA's Heat Pump Program. About half of the buildings have been double wide manufactured homes, usually around 2000 square feet with a 2 ton package unit. Installers generally removed the old furnace, disconnected any radiant, pulled the ancient (some were 20 years old!) A/C and stuck in a 15+ SEER Heat Pump. Without exception the duct systems are off the chart leakers, most of it LTO since the systems are primarily panned floor joists. Despite this, homeowners are claiming they are saving money on their utility bills and are comfortable compared to the previous set up. Imagine the savings if the duct systems were sealed up at the same time! In terms of ROI, I cannot fathom how a $6-8000 HVAC mechanical replacement cannot be improved by an additional $5-600 worth of duct sealing. These trailers are reasonably tight with so-so insulation, duct leakage should be up there on the priority list, but they don't address it at all? For several years I have been testing new homes built for the City of Knoxville by various groups that are HUD funded and require Energy Star certificates. These homes' ducts routinely test less than 30 CFM @ 25 Pa. I am seeing 250-300 CFM in these TVA Heat Pump homes. I think it is criminal to let all that potential performance go to waste. Homeowners are reluctant to do retrofits and usually don't until something breaks. If we could improve the retrofit model to include Weatherization, Duct Sealing and Insulation as well as the new Mechanicals the benefit would be double the savings we currently see. Most utility retrofit programs incentivize a more thorough approach. TVA has their Energy Right in Home Evaluation program but they make you wait a year between that and a Heat Pump, either or, but not both at once. From the "Whole House" perspective this doesn't allow for the home to get properly sealed and insulated before the HVAC is installed, the correct order of business. Why can't TVA get this together?

       One of my favorite projects is the New Norris House, a creation of the UT School of Architecture. A small, very tight home that achieved LEED Platinum. They have been playing with the passive ability by periodically turning off the HVAC and monitoring the interior tempurature fluctuations and plotting that against ambient. There is nothing technically unusual about this home, good building science with off the shell components. Interior tempuratures in moderate ambient conditions remain within a tolerable range. Imagine an '06 home without HVAC for three days! This structure was assembled by Clayton Homes and finished by UT students for the most part.
        The point is - this ain't rocket science. The question is - why are we not doing this with all of our homes?
http://www.thenewnorrishouse.com/

              There has been a discussion amongst RESNET members on Linkedin about a falsified rating. The home in question scored HERS 55 and has since been reviewed finding several components less than advertised. Should we be surprised?