The Home Energy Challenge, Pt. 1

Matt,
Nice points.  Hit the nail on the head.  Curious, you talked about retrofitting existing buildings.  How about new constructions, in rest of the world if limited in US?  How to incentivize buildings to design efficiently when payback to energy savings is to the tenants or bld. managers?  Thanks

Dan, if you fudge the numbers to fit your argument you’ll always win the argument (with yourself at least) .  Nobody should install solar with an pre-rebate installed cost of more than $3.50/watt.  Your example uses an installed cost of 6.68/watt—stupid high. 

As far as your argument that an uninsulated house should insulate.  Umm yea obviously.  Teach us something that’s not obvious please….

$10.8k for an energy retrofit that includes insulating the walls of a 2,200 sqft home? Yeah right!

25% in 20 years is minor in the end. After that 25% is achieved, what then? We need to achieve 80% by 2050, and those buildings that have been upgraded by only 25% aren’t going to go away. If you work through the numbers and consider growth in energy consumption due to population growth, the amount of natural gas used (because that is mostly what is saved by and large by the kind of efficiency improvements described in this article) in 2050 with an 80% reduction from today in California works out to about the amount of natural gas that is projected to be needed just for cooking. In other words, there is no budget for building heating *at all*.

The other problem with the example given in this article is that the numbers are based on the absolute most pessimistic scenario, a house with no insulation. This is fruit hanging so low that it is on the ground. What percent of the current built housing stock is in this category? There were probably more houses built in California in the 70’s and 80’s when insulation standards were in place but building science wasn’t as far along as today. These houses can’t be upgraded on the cheap, like this article suggests, because the walls basically need to be ripped open, the substandard or sagging fiberglass batting ripped out or supplemented, and then the walls need to be either re-sheet-rocked from inside or re-sided from outside. You can’t blow in cellulose if there is something already in the wall cavity. This results in approximately 10x the cost mentioned here, even more if you want really up to date technology like closed cell foam in the ceiling cavity.  I know this because my house is in this category and I’ve twisted the numbers on it for 3 or 4 years, and they always come up more than I have so far been willing to invest. On top of which,  your living space is disrupted for a month and a half, adding to the cost if you decide to move out.

These hard facts are the basic problem with the cost-effectiveness calculations from articles like this and the McKinsey report on efficiency. They do not consider the expense and cost of getting the kinds of real reductions that are going to actually achieve remediation of global warming. They are like the Waxman-Markey bill, lots of talk, some near term feel-good results that save money, but nothing that will actually stop it.

I challenge Sustainable Spaces and these other guys touting half-measures to come up with technology that will allow houses having substandard or sagging fiberglass batting to be upgraded in place without having to rip out the walls. Why doesn’t somebody offer a prize or something for this instead of for electric cars that get 100 mpg? In the IT industry, we regularly get substantial cost reductions and performance upgrades year over year every year, where is Moore’s Law for energy efficiency?

I added insulation with a false wall. Some is inside, where convenient, some outside where there are a lot of closets, etc.  Also, we have a basement - I put in some fans to blow summer air through the basement into the house. Cheap cooling pays for it, and there is a small but noticeable reduction in heating costs also. Forced air furnaces often have a button that turns on the fan without heat. Open the suction part to the basement, add a filter box, and push the button. There are many inexpensive options, especially for a do-it-yourself project.

You bring up a very important point: the future of a renewable world involves installing renewable energy sources and reducing consumption. Although adding fiberglass to every wall is expensive, other changes can be made: installing energy efficient appliances, sealing cracks around windows and doors, installing energy-efficient windows, and adding insulation wherever possible (blowing insulation in the walls from the attic and insulating the attic).

We do need to be doing both:  installing solar PV and retrofitting for efficiency.  I do wish that I had known more about retrofitting before I installed solar PV and hot water, but it worked out okay for me, since my PV system was sized just right to satisfy my household’s electrical usage after the retrofits were done. I spent about $2K on LED lighting, $3K on energy star appliances, $4K on insulation (1180 sq ft home), way too much ($11K) on solar hot water backed up by an on-demand gas water heater, and $20K on PV.  And, yes, if you really are looking for the best bang for the buck, CFLs beat out LEDs and doing the insulation and appliance upgrades is cheaper than doing PV (at least it WAS then—2 years ago—but with PV coming down every year, it might not always be so).  We still need distributed renewable energy generation, and PV is a great way to do that.  The main thing is that not enough folks have the foresight to realize that it isn’t just all about cost—it’s about preserving a liveable world.  We need much more public awareness of the need to conserve, and retrofitting is a great place to start.

MichaelB1: I’ve had no trouble finding takers for everything I’ve replaced. Talk to your wife about the value of passing on good used items to people who want them but night not otherwise be able to afford them.  Reusing materials and equipment keeps them out of the landfill.

Another very important thing that home owners need to be doing is tracking their energy usage. You can make all kinds of household improvements, but, after those improvements have been made, how do you know how much money, energy, and greenhouse gases you are saving each month?

GreenQuest is a free, web-based, energy management software that is extremely user-friendly, easy to use, and well designed. Simply enter your utility bill’s data (cost and usage), and as much historical data as you’re able to access. GreenQuest tracks your energy use each month, energy savings, greenhouse gas tracking, how weather affects your energy bill, where you stand against your peer group, and more. It’s a great tool to use for your home, apartment, condo, church building, business, or any other building that you’re in charge of paying the utilities.

Find out more about GreenQuest at http://www.MyGreenQuest.com or feel free to email me at (JavaScript must be enabled to view this email address) to ask questions or learn more.

Don’t be too concerned with making your house too tight. It is extremely difficult to tighten a house up too much post-construction. I find it to be more of an excuse for people trying not to tackle a job than a real possibility. After all if you start with the massive leaks first and check with the blower door periodically during the retrofit, you will know when to quit if it gets close to being too tight. I would quit airsealing before needing to spend a couple thousand dollars on an HRV.

JAK,
Regarding your comments about having to tear apart walls in order to re-insulate walls with existing fiberglass, while it might be true in some instances.  Our company was able to re-insulate 3.5 inch stud cavities that had inadequate levels of fiberglass batt without tearing apart walls.  We did not stop with the above grade walls, this $10.5K project ( energy retrofit for a 1970’s home in western WA state also included significant improvements to ceiling, floor, & duct insulation plus new continuous ventilation system that will significantly improve air quality.