There are many definitions of “green building.” For some it’s all about indoor air quality and making sure your home is not emitting fumes that are potentially hazardous to your family’s health. For others it’s about reusing what you have, renovating and making your new-old home tighter and more energy efficient. Finally there are those of us (myself included) who fall into the “embodied energy” category.
Today I watched a fantastic six minute video by Catherine Mohr who was invited to speak at TED 2010. If you can spare six minutes I encourage you to watch this funny and enlightening video on the trade-offs she and her husband consider while trying to build a green house. They have focused on trying to build using materials with the least amount of “embodied energy.” This is the link to her talk: http://www.ted.com/talks/catherine_mohr_builds_green.html
If you’re not familiar with the term, “embodied energy” refers to the amount of energy it takes to make something and therefore, that energy is considered “stored” in the finished product. For instance, according to Catherine, it takes approximately 300 Megawatt hours of embodied energy to produce the average single family home. She set out to build her own home using significantly less energy, while building a home that will in the future also use significantly less energy than the average single family home.
If we can bring each product or activity we buy or do down to the amount of energy it consumes we can make more informed decisions about which product is best. So, that being said, Catherine’s decisions led her to choose wood-framed windows over aluminum, cotton and strawbale insulations over sprayfoam. Her house will still be as energy efficient as if she’d chosen the alternatives, but she used materials that take less energy to produce and ship to her house.
Catherine has been documenting her journey on the path to building green at 301munroe.com. It’s an excellent blog, full of all of her decisions and the thought process she went through to choose each material. She also lists her trades, services, and materials suppliers (she lives in Silicon Valley).
I have to admit that after watching her TED talk, I wondered how she had done her embodied energy calculations, there are, after all, a lot of variables involved when calculating the embodied energy of a product and much depends on what type of energy is used where the product is produced (coal vs. natural gas vs. hydro vs. nuclear). Fortunately, after reading through her posts I came across the one that explains how she did her EE calculations, as well as attaching her Excel spreadsheet with the calculations. She also did another spreadsheet showing how her much energy her lifestyle consumes.
If you have a chance, look through her blog. It’s an interesting read, as well as a great resource for trades and services in the Silicon Valley area, and green products that are for the large part available across North America.