Geothermal heat pumps. Tankless water heaters. Spray foam insulation. Because of all the hype around 'green' products, it's easy to focus on the details and miss the big picture.
One problem with getting sucked into the green product hype is that some of those products are outright scams (e.g., power factor correction devices) and some are overblown (e.g., foil-faced bubble wrap duct insulation). You're mostly just enriching the companies that sell that stuff to you if you fall for it.
In the case of legitimate green products that make your home perform better and save money on your energy bills, it's possible again to get little or no benefit from them. For example, I'd much rather have a 13 SEER air conditioner on a great duct system than a 19.7 SEER air conditioner on a typical duct system.
If you're buying, building, or involved in any way with the creation of a high performance home, here are some guidelines to help you not lose sight of the forest for the trees:
- Get a home energy rater involved to do energy modeling of the house before you start building or renovating.
- Focus on the building envelope. Make sure that the insulation and air barrier can really do their jobs so you minimize the amount of heating and cooling the house needs.
- Make sure the HVAC system is designed well, installed properly, and commissioned.
- Put in a high efficiency or solar water heater, but don't forget about the distribution system. Minimize the length of the hot water lines by clustering bathrooms, kitchen, and laundry.
- Use natural light, compact fluorescents, and LED bulbs to reduce your lighting costs.
Let me state this again: It's not about the products. It's how it all works together that matters. I know that mastic, caulk, and insulation installed to grade I aren't as sexy as geothermal heat pumps and photovoltaic modules, but the basic design details, material choices, and installation methods are actually a lot more important than the trendy 'green' products.