Too soon for solar
While I would love to have solar panels on my roof harvesting the sun's energy to power my home, I cannot yet justify the investment. A kilowatt of power costs about $6,000 to $6,500 installed. A few years ago, the same kilowatt of power would have cost $8,000 to $10,000 to install. So, the good news is the downward trend in pricing is making solar panels more affordable. But, it is important that I stop and think about what my investment is funding.
A couple of weeks ago, I met with lighting reps who sell LED lamps. They arrived in my office with five different types of lamps, most rated at 8 watts. Their visit was precipitated by a lighting study we did on our office - a thirty thousand square foot space lit predominantly with T8 fluorescent fixtures, but also highly populated with track lighting to illuminate architectural drawings on our latest work hung on high walls throughout the building. Our study showed that if we completed a retrofit of the track lighting from halogen to LED lamps, we could reduce the electricity we are consuming for lighting by one third.
Here's the math on this transaction. We have a total of 250 spot lights. At 100 watts apiece originally (150 have been changed over to LED to date), 25 kilowatts of solar power would be required to light those fixtures with clean power at an estimated cost of $150,000. If those 250 lamps were 8 watt LED lights instead, the same lights could be powered by 2 kilowatts at an initial investment of $12,000. Of course, the cost of LED lights is significantly higher than the halogen lights. I have seen pricing range from a low of $32 per lamp upwards to $65 per lamp. Sticking with the low end of the range, the initial investment to retrofit all of the lamps would be $8,000. So, total first cost is $20,000 versus $150,000 (not including cost of halogen lamps).
Of course, in my home, the numbers are much lower. I'm waiting for delivery of 24 new LED lights that are dimmable, come to full light level as soon as I switch the fixture on, have good light output, and have a warm color light unlike the cooler color light temperatures favored in commercial settings. Those lamps are costing me less than eight hundred dollars. The total wattage of all that lighting power will be less than 200 watts. Incandescent lighting at 100 and 50 watt lamps would be ten times that demand or 2 kilowatts. Spend $800 or $6,000? I think the choice is clear.
As you might guess, I'm retrofitting most of the lamps from CFLs not incandescent lights. I ran out and purchased dimmable CFLs when they became available on the market. But these lights only dim in incremental steps, and flicker out when I try to dim them down as low as I'd like. The light output of the LED is far superior, they do not contain mercury and they have a longer lamp life over the CFLs. But, I would recommend not rushing out to change over your lighting to LED without buying and testing the different lights one at a time. There are a lot of companies entering the marketplace with this technology which will continue to make them more and more affordable.
I recommend that you ensure that the LED lighting from one lamp to the next is consistent and that the color of the light is what you desire. For instance, I tried a lamp replacement for a table lamp. The bottom half of the LED version was opaque which meant that the light was only being reflected up, not down - the desired direction for most table lamps and the light output was too low to overcome the lack of downlight. Other lights I have need a light source that makes the fixture glow and I have yet to find an adequate replacement. But, I am confident these lamps are going to be available in the near future and I am keeping a look out.
I still would like to find an affordable way to put solar power on my house, not to power wasted energy like the electricity required for incandescent lighting, but to power the electric car or plug in the hybrid I hope to purchase next (I currently drive a Prius). But, there is a problem with a plug in hybrid. If you plug in to a dirty power source from your distributed power, are you really helping the environment? A solar array to power an electric car?That makes more sense to me!