Sunday, August 26, 2012

Michael Sadler: Paying twice for home energy -

Michael Sadler.

Michael Sadler.

I received various responses regarding the previous column on saving both energy and money in the home. A coffee buddy put up a clothesline, took a picture of his laundry, and posted it on Facebook.

A colleague mentioned that a clothes dryer vents the heated air to the outside and the replacement air must then be cooled during the summer. Another consideration is the heat given off by the dryer while it is operating. Both cause the air-conditioner to work harder, so should be added to the cost of operating the dryer.

He asked me to estimate this additional cost. The answer depends on the inside and outside temperatures and the rate that the air is vented. An upper limit is to assume that the air-conditioner must remain on while the dryer is operating. My air-conditioner consumes about 4 kilowatts (kW) of power, which comes to 40 cents per hour at $0.10/kwh. The bottom line is that, during the summer, it makes more sense to run the dryer when it's coolest outside (night or early morning).

ERCOT (Energy Reliability Coalition of Texas, which operates the electric grid and manages the deregulated market for most of the state) will also thank you since it reduces the peak load. By all means, avoid the hottest hours of the day, usually 3-7 p.m. To my knowledge, ERCOT had no rolling blackouts this summer when supply could not meet electrical demand, but there were some days when the cushion was thin.

I mentioned last month the energy savings of fluorescent lighting compared to conventional incandescent bulbs. Only 5 percent of the electrical energy of an incandescent bulb is converted to visible light. The other 95 percent is radiated as heat. This heat load must be overcome by air conditioning during the summer, meaning that one pays twice.

I recently experienced a bathroom in which a large mirror was illuminated by eight 100 watt bulbs. While it was great for shaving (except for the noticeable rise in temperature in the small space), the equivalent light output could have been achieved using fluorescent lighting with less than one-fifth of the heat output. If the lights were inadvertently left on, the cost would be 8 cents per hour, plus the cost of running the air-conditioner to overcome the heat load. On the other hand, no bathroom heater would be needed during the winter.

Another reader sent me an email saying she read the article and was concerned about the surcharge that appears on her bill when her usage falls below 500 kwh. For that, she is charged an extra $6.95/month. My previous power provider charged $7.95/month whenever I used less than 1,000 kWh, an amount that I surpassed in July for the first time in a year. I had not noticed the charge in the fine print when I contracted for electricity a year ago. I changed providers and have been assured that there is no charge if I "fail" to use a certain amount. The charge is counterproductive since it discourages conservation and can increase the average rate by about a cent per kwh.

One can shop for electricity marketers and compare rates on the web at One can choose a fixed, variable or indexed plan as well as renewable energy content. A CSV (Microsoft Excel) file can be downloaded that lists rates based on monthly usage of 500, 1000 and 2000 kwh.

Energy awareness helps us to decrease our consumption and save money with little or no decrease in comfort or convenience. Collectively, we can make a huge difference. If we can eliminate the need to build additional polluting coal-burning power plants, we'll all be better off.

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