In a recent post I asked, What the heck is a net zero energy building? I am still confused about the detail, but the basic concept is straightforward: a building that produces as much energy as it uses. There are two ways to get to zero: add more supply or reduce demand. There are many ways to reduce demand, and they can be pretty boring compared to shiny solar panels on the roof.
That’s why I was impressed with an infographic promoted by Vivint, a security company that has morphed into a smart home company. They could have filled it with all their smart locks and lighting controls and security systems, but instead they cover the solid basics that should be done first. They also did something you don't always see on infographics: A sources button at the lower right so that you can verify the information or get more. It’s all from reputable sources, although some are a bit out of date. It’s not “embeddable” because of the format, so you can get the lay of the land in the image above but you'll need to click here to see the real infographic and get their 10 points.
I have some supplementary comments (and some minor criticisms) to add to their recommendations, with links to our own posts on the same subjects.
1. Install effective insulation.
Heating and cooling can eat up more than half the energy used in a home. If you can get at an attic and add more, it can make a huge difference. Walls are tougher and more expensive. I would have also suggested caulking and air sealing here as well; a lot of heat gain and loss is through leaks. Choice of insulation is one of the toughest issues in green design, with questions about embodied energy, health and safety.
If you want to know more on this topic, we've got you covered:
2. Go double-glazed with high-performance glass.
Windows are really expensive and the savings in energy gained by replacing them is almost always overestimated. However there are many reasons why people do it beside just energy, including maintenance and aesthetics. The right glass is really important. In some parts of the country you want to maximize solar gain; in others you want to minimize it to reduce cooling costs. But be careful — changing windows isn’t always appropriate.
3. Heat and energy recovery ventilation
Switching to an Energy Star rated furnace can save money, especially if you are able to resize your unit after insulating and sealing. If you've done a good job of sealing your house, then an energy recovery ventilator (ERV) is a good idea to maintain air quality. But it's the sealing, not the ERV, that saves the money. The ERV controls moisture that builds up in the air by controlling ventilation, and it recovers the heat lost in the air being exhausted.
4. Change your water heater
Energy Star approved water heaters save a lot of energy. New ones use heat pumps and draw heat out of the air, which saves a bit on cooling the home while heating the water. Tankless water heaters save money because it's only heating on demand, but they are only really an option if you have gas. Solar hot water makes sense in the south but is falling out of favor everywhere else.
5. Electric or gas power vs. solar power
The cost of solar power keeps dropping; this has become a no-brainer in most of America. However solar panels don’t store energy, they just make it, so most people are still tied to the grid.
6. Traditional vs. programmable or smart thermostat
Interestingly, The better your house is built and insulated and sealed, the less a smart thermostat will save you as the heat losses and gains are so much slower and lower. But if you're in the kind of house that the furnace or air conditioner is running all the time as you heat and cool the outdoors, it can make a big difference.
7. Get a new toilet
This has absolutely nothing to do with net zero energy, but it should be done anyway. There's more to the environment than just energy and water is a critical issue. That's why I'm pleased to see this item here; we should be going net zero water too.
8. Incandescent bulbs vs. compact fluorescent lighting (CFL)
Get rid of incandescents, definitely, but don’t get CFLs. LED lighting has dropped in price so much that there's no reason to buy a CFL. They don’t last as long and don’t give as nice a light, and so many smart technologies are coming that work with LED but not with CFL. Plus, there's no mercury in them, although that was more politics than problem.
9. Mindful vegetation
YES! This is a point that is so rarely mentioned, how we can work with nature to reduce our energy costs and our carbon footprint. A properly placed deciduous tree is the most sophisticated energy-saving device you can buy; it shades the house in summer and lets the sun through in winter. It eats carbon dioxide. It transpires moisture into the air, absorbing heat. It makes you happy.
10. Reflective or light roofing
Savings will vary, and I've had many arguments with roofers about how much it can save, particularly in the North. But the point is, the hotter our climate gets, the more sense this makes.
Really, Vivint could have been a lot more aggressive in promotion of its own products here; they didn’t even mention the Sky smart home system. That’s why I like this; they go for the basics first. Good for them.