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Solar Power Improves Efficiency of Outdoor Lighting


Question: I want to try some solar-powered lights for landscaping and walkways. Do the newer ones provide more hours of light than the old ones? Are they brighter?

Answer: Although most solar-powered kits are not as bright as low-voltage lights, the newer solar ones provide adequate light for highlighting plants, marking a path or security. The major advantage is you just stick them in the ground with no wiring and you can move them at anytime.

The advances in solar cell and battery technology allow more of the sun's energy to be converted to electricity and stored in the batteries until nighttime. At the beginning of summer, when the days are longest, the new solar-powered lights will stay lighted brightly throughout the entire night.

Although the size of the solar cells built into the light is important for charging the batteries daily, don't just compare the cell sizes when shopping. The newer technologies of solar cells produce more electricity with smaller size.

There is a variety of lighting styles from various manufacturers available. Some new decorative models are made of die-cast metal for durability and styling detail. Several lantern styles can either hang from a 27-inch riser or mount on a post.

Not only are the solar cells and batteries better, but the newer designs use more efficient and brighter bulbs. LEDs (light-emitting diodes) are the most efficient light source, and the bulbs last a long time. They are available in white or amber light. Amber light attracts fewer insects.

Fluorescent bulbs are also efficient and brighter than the LEDs. They are typically about five watts. Halogen bulbs are the brightest and produce a very white light. They are often used in motion-sensing lights, which are not on continuously.


Air-Conditioner Tuneup Can Increase Cooling

Q: My house has central air-conditioning, but I also use a window unit in my bedroom. Neither cools as well as it used to, and my electric bills were high last summer. How can I maintain and tune them?

A: Although a central air-conditioner should be professionally serviced about every three years, there is some annual maintenance you can do. A springtime checkup should cut an air-conditioner's operating cost by 10% or more and provide more cooling capacity.

You will find a greater improvement in performance and efficiency by servicing your window unit. These systems are sensitive to dirty air filters and debris inside the housing.

The key to keeping your central air-conditioner operating efficiently and producing its maximum cooling output is to make sure the air flow through the outdoor coils is not impeded. If the coils cannot easily transfer heat to the outdoor air, the unit must run longer and uses more electricity.

First, check the clearance around the outdoor unit. Shrubs can grow quickly and the foliage can get too close. A 3-foot clearance is usually adequate. Some outdoor units are side-discharge and others are top-discharge, so check the clearance in the proper direction.

Switch off the electric power at the indoor breaker box or at the unit itself. Remove the sheet-metal screws and lift off the housing. You may find leaves, sticks, toys, etc. in the unit. Clean out the debris.

If you find coil fins bent over, straighten them as well as you can with the tip of a sharp knife. Replace the housing, carefully tighten all the screws, and make sure all the sheet-metal parts fit tightly. It is important for the fan to draw air through the coils and not through gaps and cracks.

Planting some shrubs reasonably close to the unit provides shade and cools the air around the unit. This improves efficiency.

Then, go indoors to your air-conditioner blower. Clean or change the filter because maximum air flow is important there too.

While the filter is out, use your vacuum cleaner brush attachment to reach cooling coils.

Pop off the front of your window air-conditioner to remove and clean the cooling air filter. Remove a few sheet-metal screws, and you should be able to remove the housing. Remove debris and wipe off the blower and condenser fan blades.


For more information on solar lighting, download Update Bulletin No. 514 at For air-conditioner tune-up details, download Update Bulletin No. 803.

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