March 18, 2011

What the heck is a "degree day"?


The new tally of “degree days” on our print weather page is puzzling some readers. Degree days measure neither degrees, nor days. It’s a proxy for estimating the energy used to heat or cool our homes and businesses. They’re calculated by comparing the previous day’s average temperature with 65 degrees. An average temperature of 75 degrees in summer yields 10 cooling degree days. An average of 35 in winter gives us 30 heating degree days. The more degree days, the thinner your wallet. 

(PHOTO: Christopher Furlong, Getty Images, 2008)

Posted by Frank Roylance at 12:01 AM | | Comments (0)
Categories: Saving energy

September 23, 2009

Nasty humidity; I want my AC

I admit it. After weeks of blessed fresh air and breezes through the house, Wednesday's summer-like humidity got to me. Tonight, I switched on the AC.

Hot and sweaty/FlickrI know. I know. We were saving a bundle having the AC off for weeks on end, through what's been mostly a delightful September. And we might have lasted until Nov. 1 without turning on the AC or the heat and handing over our paychecks again to BGE.

But trust me. By the time I got home tonight, the temperature upstairs was 81 degrees, with a relative humidity of 88 percent. My wife was, um, glowing. The stuff in the fridge was sweating. All the windows were open and it provided no relief at all. The humidity had been even higher Tuesday night - as much as 99 percent on the WeatherDeck.

So I caved. I kicked on the new Bryant. Now there's a cool, dry breeze in the house, stirred by fans. And all is well. May even throw on a blanket tonight.

This weakness of mine should only last a day. Temperatures by Friday and Saturday will be cool, near 70 or even lower. And dry. We'll open up again and breathe freely once more.

So how long can you hold out this autumn before you turn on the heat?  

Posted by Frank Roylance at 8:49 PM | | Comments (5)
Categories: Saving energy

March 26, 2009

It takes green to go green

After a brutal winter on the energy front - everyone's electric bills soared this winter - it's time to take stock. While December and February were relatively mild, January ended 3 degrees below the long-term averages. Heating degree-days, a temperature-based measure of heating demand -  are running 7 percent above average. So, it's the season to take a look around and find ways to cut down on energy use in the future.

I'd like to get a discussion going here about how readers are dealing with their energy consumption issues. Perhaps you're feeling depleted by this winter's high bills, and you're looking for ways to conserve energy. Maybe you've already converted to solar, or geo-thermal and you're reaping the rewards in the form of lower utility bills than last year. Maybe you've found simple, low-tech ways to tighten up your house and now you're seeing some payback.

Sun Photo/Elizabeth MalbyDrop us a comment and let us all know what you're doing and how it's working out. Ask questions, and maybe I can find an answer, or another reader can chime in and help.

I'll start. After 12 years in our townhouse, and some of the biggest winter utility bills we've seen, my wife and I decided it was time to replace the old heat pump. It serves the second floor and loft (we have gas heat on the lower floors). It still ran. But it had developed a noisy clatter, seemed to run a lot, and our HVAC guys said it was going to need $400 or $500 worth of work.

There were other problems. To start with, it was, from the beginning, a cheap builder's model, with the lowest energy efficiency ratings available at the time. Our bedroom, in the rear, was frequently 10 degrees colder than the front rooms. The heat pump just was never up to the task when temperatures fell much below freezing.

Knowing that heat pumps - at least the compressors - typically have a 10-year life expectancy, we decided it was time to get a new model. After some discussion with our contractor, we decided on a high-efficiency, Energy-Star model from Bryant. In addition to some energy savings, it comes with the promise of a $1,500 credit on our 2009 federal tax return, knocking the effective price down to about $4,500. Ouch, but ...

Continue reading "It takes green to go green" »

Posted by Frank Roylance at 10:25 AM | | Comments (7)
Categories: Saving energy
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About Frank Roylance
This site is the Maryland Weather archive. The current Maryland Weather blog can be found here.
Frank Roylance is a reporter for The Baltimore Sun. He came to Baltimore from New Bedford, Mass. in 1980 to join the old Evening Sun. He moved to the morning Sun when the papers merged in 1992, and has spent most of his time since covering science, including astronomy and the weather. One of The Baltimore Sun's first online Web logs, the Weather Blog debuted in October 2004. In June 2006 Frank also began writing comments on local weather and stargazing for The Baltimore Sun's print Weather Page. Frank also answers readers’ weather queries for the newspaper and the blog. Frank Roylance retired in October 2011. Maryland Weather is now being updated by members of The Baltimore Sun staff

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