Digital cameras are useless when their batteries run dry. Battery technologies have improved a lot in the last years but batteries still have just a limited energy capacity. To get more out of your batteries you should understand what digital camera feature consumer more power and how to minimize energy consumption.
Not all camera elements consume the same amount of energy. You can save battery energy by minimizing usage of battery energy guzzling features. The following is a list of battery hungry battery features minimizing usage of those features will provide you with longer battery life.
The digital camera elements can be divided to electronic and mechanical. The chipset and the CCD for example are electronic while the lenses focus motors are mechanical. Generally speaking mechanical elements tend to consume more energy than electronic elements for the same amount of usage time. The exception is the LCD screen that is an electronic element but is also a battery hungry one.
Here is a list of three components that consume the most energy in a typical digital camera and some ideas for how to minimize their consumption.
The LCD screen: Digital cameras allow viewing of digital photos immediately after they were taken on a small bright LCD screen built into the camera. This allows you to review the digital photo composition and to decide if the digital photo is good or if you need to take more photos. LCD screens are also convenient when used as view finders. You can use the LCD to see a real time view of the picture the camera is capturing and then hit the shutter button when you got the digital photo you are looking for. The drawback of the colorful bright LCD screen is that it consumes a lot of energy. If you ever wondered why those LCD screen are turned off automatically by the camera it is to save energy as if they were left on all the time the battery would last a very short time. To save battery try to minimize the usage of the LCD screen. If you have an optical view finder use it whenever possible instead of the LCD. Manually turn off the LCD and only turn it on when absolutely necessary to either access some digital camera menus or to preview a digital photo.
The motors: The digital camera mechanical components are powered by electrical motors. For example an auto focus is implemented by motors that move the lenses in and out. Some digital cameras also include motors that let the photographer control the zoom factor with a press of a button. Motors are electro-mechanical components. They are high energy consumers. The bigger and heavier the lens, for example using high zoom telescopic lenses, and the optical elements that the motor has to move the more energy is consumed. To minimize battery consumption move the digital camera components manually whenever possible. For example if the camera supports zoom in zoom out buttons avoid using them and instead manually move the lenses ring to change the zoom. Try to focus only when you are ready to take a digital photo. Avoid using continuous focusing and holding the shutter button half way for a long time as the motors will keep moving and consume energy during all that time.
The flash: Flash is used when taking digital photos in dark scenes or as fill-in when there are shades on the objects. Flash is an electro-optical component. Energy is charged into a special electronic component and later on that energy is discharged in a short time in the form of light energy. In general the brighter and longer distance a flash unit supports the more energy it consumes. Avoid using flash in scenes where there is enough ambient light.
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