Here's some reasoning on the energy savings ...
http://tf.nist.gov/general/daylightsavingtime.html
One of the biggest reasons we change our clocks to Daylight Saving Time (DST) is that it saves energy. Energy use and the demand for electricity for lighting our homes is directly connected to when we go to bed and when we get up. Bedtime for most of us is late evening through the year. When we go to bed, we turn off the lights and TV.
In the average home, 25 percent of all the electricity we use is for lighting and small appliances, such as TVs, VCRs and stereos. A good percentage of energy consumed by lighting and appliances occurs in the evening when families are home. By moving the clock ahead one hour, we can cut the amount of electricity we consume each day.
Studies done by the U.S. Department of Transportation show that we trim the entire country's electricity usage by about one percent EACH DAY with Daylight Saving Time.
Daylight Saving Time "makes" the sun "set" one hour later and therefore reduces the period between sunset and bedtime by one hour. This means that less electricity would be used for lighting and appliances late in the day.
We also use less electricity because we are home fewer hours during the "longer" days of spring and summer. Most people plan outdoor activities in the extra daylight hours. When we are not at home, we don't turn on the appliances and lights. A poll done by the U.S. Department of Transportation indicated that Americans liked Daylight Saving Time because "there is more light in the evenings / can do more in the evenings."
Daylight Saving Time also saves a small amount of energy in the morning when we rise. Studies show that 70 percent of all Americans rise prior to 7 a.m. during the work week. During the summer months, sunrise is very early in the morning, so most people will wake after the sun rises. Because the sun is up, we will turn on fewer lights in our homes. Thus, we actually use less energy in the morning.
So, we save energy in both the evening and the morning because we use less electricity for lighting and appliances.
In the winter, the afternoon Daylight Saving Time advantage is offset by the morning's need for more lighting. In spring and fall, the advantage is less than one hour. So, Daylight Saving Time saves energy for lighting in all seasons of the year except for the four darkest months of winter (November, December, January and February) when the afternoon advantage is offset by the need for lighting because of late sunrise.
I guess being in Northwest North Dakota, I have a latitude bias. By winter, it will only be daylight from about 8:30 AM to 6 PM, in summer, dawn comes around 5 AM and dark as late as 11:30 PM. To me, changing the time change is just a pain in the hindparts, compounded by living in one time zone and (mostly) working in another.
Stereos use more juice at night?