Archive for the ‘lighting’ category

Quick Tip #37 – Can Lights? Make Them Green

October 27th, 2014

Can lights or recessed ceiling lights are a common design feature in modern residential construction. They are also common in older custom-built homes. They provide a unique lighting pattern without the glare of a fixture, but they may also waste energy.

You have several options when replacing the bulbs (lamps) in can lights. Don’t use a common “A” type bulb; it will not direct light out of the fixture. Most of the light is just wasted inside the can.

Consider a spot or flood lamp that reflects and projects light out of the can, such as a parabolic aluminized reflector lamp (also called a PAR bulb). For a “green” step up, consider a parabolic lamp, which has a curved reflector that projects even more light out of the can into a smaller pattern.

For a choice that’s even more “green,” use a compact fluorescent spotlight or reflector lamp. These compact fluorescents save about 75 percent in energy costs and last much longer than incandescent bulbs. They also create less heat in the room – heat that must be removed with air conditioning in hot climates.

While light from fluorescent lamps may look a little different at first, their light color and quality have greatly improved in recent years. Look for “warm” color lamps or “color corrected” lamps for a more pleasant light.

E123C - Can Lights - Proper Bulbs_300dpi

Candle Soot: Shadowing and Ghosting

April 13th, 2013


Two years ago, we installed a new roof with ridge vents. Recently, we have noticed shadows on our ceilings in places where the roof trusses run. The house has cathedral ceilings as well as flat ceilings, and these “shadows” show up in all rooms. Also, along an exterior wall in our kitchen, we can see (from end to end) the outline of the roof truss, as well as vertical markings of studs. The markings in the ceiling and the walls look like someone lightly penciled in shadows of the trusses and studs. Can this be a result of the ridge vent that was cut in the roof?



What you are describing is textbook “shadowing” or “ghosting ” from candle soot. Does someone in your family burn those nice aromatic candles in glass jugs? Those are great soot producers.

M049 - Candle - Soot Generator


Candle soot is about as heavy as air. It moves throughout your home, aided by the forced air furnace. Outside walls and attic ceilings have plenty of insulation, but there is much less insulation on the framing edges. As a result, framing edges and fasteners are slightly cooler than the surrounding drywall.

When the air moves across the cooler surfaces, it slows slightly and deposits soot. The dark soot stains outline the framing with a shadowy or ghostly appearance.

So, stop burning candles! Or at least burn only very high-quality candles, and keep the wicks trimmed to 1/4 inch or less. Don’t burn candles in jugs – their combustion is starved of oxygen, so it produces lots of soot. You can find more information at in the Free Articles section; look for the article, Soot, Ghosts and Ugly Stains.

M050 - Candle - Trim Wick


Energy Efficiency Improvements – Where to Start?

August 21st, 2010


I have some funds to do energy efficiency improvements to my old (1950’s) home, but I don’t know where to start. The home is well maintained, but has had no energy improvements. It seems that every contractor has the best product, and there are many claims about huge energy savings. The government rebates and tax credits just seem to complicate the issue. Where do I start?


There is no simple answer. I can outline where to logically start, but I think your home deserves an evaluation and some scientific testing before you start spending.

I suggest you contact Focus on Energy. Their goal is to provide information, resources and financial incentives to help improve energy efficiency in Wisconsin. The state program is well known throughout the country.

I used the Focus on Energy program called “Wisconsin Energy Star Home Program” when I built a new home. They gave advice on construction details, and worked with the builder on energy efficiency. The results were fantastic.

For existing homes like yours, they offer a service to scientifically evaluate your home and the systems in your home at a very reasonable price. Their consultants can test for leaks, review your equipment, and use a computer model to identify the best areas to invest.

Overall, you should look at the easy energy improvements and your old equipment. If you have a furnace that is over 25 years old, put that at the top of the list. If the attic insulation has never been improved over the original three to six inches, that should be high on the list as well. Insulating the top of the basement wall, using low-flow plumbing fixtures, fluorescent lamps, and a set-back thermostat are simple changes with a great payback.

An evaluation by the Focus on Energy is the best first step. They also offer a new interactive website at Ask Focus on Energy. They will answer your questions and refer you to a large database of answers. If you have a unique question, one of the experts can respond.

Saving Energy With Fluorescent Lighting

June 29th, 2010


I am trying to find some info regarding the power usage of fluorescent ballasts. I was told that it takes more electricity to energize a ballast initially than to run the light for a few hours. I don’t know if that’s true with the new rapid-start/electronic ballasts. Is it going to save any energy to turn off office lights for an hour, then turn them back on?


Great question! Most folks don’t realize all the modern changes in fluorescent lighting. The ballasts are now electronic and this dramatically changes performance and efficiency. Remember the days of the old “starters” (the little aluminum can inside the fixture)? Modern fluorescents have a starter built into the ballast. The ballast is used to energize the lamp and start the flow of electrons.

In studies I have read, you should always turn off the lights when they are not needed, even if only for a few minutes. The calculations show that the energy used to start the lamp is saved in a few minutes of operation. The on-off cycles really do not affect the life of the newer florescent lighting. Sometime a “few minutes” can turn into a few hours, so always turn the lights off.