Recently, in addition to working with Joe on HVAC and insulation options I have spent time considering various lighting options. Ultimately we want to get the Lambertville house, and others that SquallCo creates, to be very energy efficient. There are two main motivations for this: ongoing operating cost and carbon emission reduction.
The options for light bulbs have gotten more complicated over the past several years, but that is a good thing. The traditional 100 watt incandescent bulb is being phased out by CFL and LED bulbs that can save around 75% in energy use and costs compared to traditional bulbs. There are also halogen incandescent bulbs that are about 25% more efficient than other traditional bulbs.
It is clear that using the newer technology in bulbs is an obvious choice. Though they are more expensive, the operating expense is considerably less. They last longer, cost less to use, need less energy, and have significant environmental benefits.
There are, however, some negatives. CFL’s are essentially fluorescent light. While there are options on the market that are less harsh than others, and shades, etc., can help mute the bright light, they don’t create the greatest quality of light for some applications. Most of them won’t dim, either. LED’s are considerably more expensive than either halogen or CFL’s for both the housing and the bulbs. They do last longer, emit nicer light, and can dim; but the upfront cost (while expected to come down over time) may be prohibitive for many homeowners or builders.
To better make the choice, I started thinking about how much energy lighting uses in a house. There are varying opinions on this, but the general consensus seems to be around 10-12% of total energy consumption in a “typical” home is used for lighting. I am sure that this can and does vary significantly by region, home design (daylighting can basically eliminate the need during the day in many areas), and personal usage. However, in terms of rank-order, lighting seems to clearly lag behind heating and cooling (combine for a whopping 46% of total energy usage / cost), water heaters (14%), and appliances (13%). In fact, if you look at the government data on this, you could reasonably determine that lighting isn’t all that significant in the overall effort to reduce energy use and expense.
Given that the average US home spends around $3,500 a year on energy (again, this obviously varies greatly), the typical portion of someone annual bill for lighting is around $350. Optimally, if you used all LED or CFL lights and saved 75% you would reduce your lighting cost to +/- $87.50 annually and save around $262 per year. Over 10 years that’s $2,625. For many people already living in a home, switching out light bulbs is probably the easiest way to reduce their CO2 footprint and reduce their costs. If you’re building a new home or gut-rehabbing an existing house, lighting probably isn’t as large of a concern, relative to other improvements that can be made. At the same time, it’s relatively low hanging fruit to reduce costs and consumption, and well worth the time to get it right.
My research in this is not-yet-complete. But the synopsis is that CFL’s with some exceptions that I need to better understand, don’t offer the quality of light that I want and that LED’s can be very expensive - perhaps too expensive to do in mass. This post has already gotten too long, and I have more research to do anyway. On my next post on this, I’ll breakdown the costs of CFLs and LEDs and try and articulate my philosophy and which to use where.
Increasingly my thinking is that the right approach may be to combine halogen (-25%) with CFLs and LEDs (-75%) in the home based upon areas of usage. I am not sure that the “bang for your buck” is good enough financially (LEDs) or aesthetically (CFLs) to only use either. I’ll post again later this week as my thinking on this evolves.
