Alkaline batteries have been around for a longtime. Many people don't realize how many they use each year. The cost to purchase alkaline batteries is more than just the cost of the initial purchase. The costs add up over the life of a battery. From buying to trashing the alkaline battery is more expensive if you stop and take a quick look at it.
A pack of AA batteries may cost $5 for eight batteries. Now how long do they last is a long and difficult question to answer. In a TV remote they might last 6 months. Put them in a digital camera they might only last three pictures. Some might think that is an exaggeration but it really isn't. Some cameras will not work unless the voltage is at almost the peak voltage. So just think about the cost of batteries with that in mind.
Taking a mathematical look at batteries levels the playing field. Say a AA battery is 2000maH, this is the batteries rating of how much energy it has. Not all batteries have the same maH rating due to chemical formula variations. The problem with alkaline batteries lie in the formula used to make them. As they are used the voltage that is supplied by them deceases linearly with time. Once your device no long receives the minimum voltage that it expects the device no longer works and will turn off or not function the way it is designed to.
A NiMH battery is a type of rechargeable battery. Other types of rechargeable batteries are Ni-cad, and Lithium Ion not to be confused with Lithium batteries which are not rechargeable. Ni-cad batteries are commonly found in those RC car battery packs because they are cheaper. They suffer from memory effect as most people call it and many remember and hate them. Ni-cad batteries are the main reason that most people do not like rechargeable devices. NiMH batteries do not suffer from this problem and so last much longer. A NiMH battery with a 2000maH rating has the ability to last just at long in any device. The change comes from the way the batteries work. Unlike Alkaline batteries that have their voltage decrease linearly with time NiMH batteries hold their voltage to almost peak. Once the NiMH battery reaches the end of its charge the batteries voltage drops.
The difference between the two types of batteries greatly effect the cost. Some of those alkaline batteries being tossed are fine for your remote just not your camera anymore. Tossing all those batteries is very costly as many alkaline batteries never get fully discharged.
Another cost factor is alkaline batteries are one time use while a NiMH is rechargeable. Being able to recharge NiMH batteries is huge cost saver. A NiMH battery can be recharged more than 200 times. Looking at that in comparison 200 Alkaline batteries would cost about $100. That is a lot of money to spend on batteries. Yes recharging the NiMH batteries cost money also but lets see how much. Watts is Voltage times Current, so 1.2Volts X 2 Amps = 2.4 watts. A Kilowatt hour costs on average 17 cents. 17 X .480 Kilowatt hours = .0816 cents. That is a savings of $96.21. That is huge and with only one battery. How many things use just one battery. I don't have many items that do that.
From just some simple math it is easy to see the savings that are possible from using Rechargeable batteries. Not only do you save money. You buy less, but you also throw out less. Spending money on trash removal is pricy also, and landfills have only so much room. Keeping it out of the landfill saves the environment and that is a green part or rechargeable. Not to mention less chemicals in the creation and less chemicals in the landfills.