Go Green in Your Home

Calculate How Much Money You Can Save with Rechargeable Batteries

Now for those of you that would like to enter different numbers and specifications for different batteries you can do so with the calculator below and it will calculate the same calculations I’ve done above for my battery usage and choice of batteries. You may save more money if you use more batteries at a time than I do. If you’re interested in learning about this comparison scroll down passed the battery calculator.

Which is Battery is Cheaper for You?

Cost per kWh: (found on your electric bill) Average is $0.13/kWh Used to calculate cost of charging.
	Rechargeable Batteries	Disposable Batteries
Cost of Batteries:
Batteries/pack:
Capacity in mAh:
Charge Cycles:
Cost of Charger:
Input Power Consumption of Charger (watts):
Hours to Charge:
Batteries Charged @ Once:
Number of Batteries Needed @ Once:

If you’re reading this go green article on which batteries are more cost effective, rechargeable batteries or disposable batteries, then I’m guessing you are wanting to save money! Saving money is easy to do if you follow the go green tips on GoGreenInYourHome.com!

Which Battery is Cheaper?

There have been many people wondering which batteries are cheaper to use, disposable batteries or rechargeable batteries. Well if you are the type of person that just wants the short answer and leave, the answer is rechargeable batteries are cheaper to use! If you are the type of person that wants to see the research, proof, and specifications, continue reading to see why rechargeable batteries will save you money and how much money rechargeable batteries will save you.

Which Battery is Better for the Environment?

If you are wanting to know which batteries are better for the environment, the quick and easy answer is NiMH rechargeable batteries. When your rechargeable batteries finally don’t hold a charge anymore, they get disposed of and there is only 24 of them (in my examples below) versus 4,430 alkaline batteries getting disposed of! Yes, 24 NiMH batteries are equal to 4,430 alkaline batteries. Keep reading to get the explanations of why NiMH rechargeable batteries are better.

Battery Research Information Summary

First of all I have tested and researched information for this go green article using some of the more cost effective AA alkaline disposable batteries and some cost effective AA Ni-MH (nickel–metal hydride) rechargeable batteries. I also will be using the lower end of the charge cycles for the Ni-MH rechargable batteries, so I don’t have anyone saying “You will never recharge Ni-MH batteries that many times”. I have not tested the charge cycles on Ni-MH rechargeable batteries, I had to research this information online as I do not have time to do that many charge cycles on my NiMH rechargeable batteries. I found that rechargeable NiMH batteries can be charged anywhere from 200 – 800 times! I have personally charged mine at least 50 times so far and they are still working perfectly fine.

Your Own Battery Calculations

Also for anyone that would like to enter their own numbers to see which type of batteries are cheaper, I have a calculator at the top of this article that you can use to calculate which batteries are cheaper for you. You can enter your own battery prices, charge cycles, cost of charger, amount of batteries used at a time, etc. and all the math calculations will be done for you!

Battery Research Details

Now for all the details, research, specifications to show why AA NiMH rechargeable batteries are cheaper or more cost effective than buying AA alkaline batteries.

	AA NiMH Rechargeable Batteries	AA Alkaline Disposable Batteries
Cost of Batteries:	$18.99 for 8 ($2.37375 each)	$12.49 for 48 ($0.2602083333 each)
Capacity:	2,400 mAh	2,600 mAh
Charge Cycles:	200-800	1
Charger Cost:	$14.99	$0.00
Charging Cost (Electricity):	$0.0013121875/battery/charge cycle	$0.00
Number of AA needed at once:	24	24

Battery Calculations Explained

Now that we have all our information needed in the table above, let’s do some calculations to show why NiMH rechargeable batteries are more cost effective than alkaline disposable batteries.

Cost of Rechargeable Batteries

We need to figure out how much it costs to get all the rechargeable batteries needed. I need 24 AA batteries in my home to be used at once. This is putting a battery in all my devices that need batteries. If you want some extras to have as backups so you don’t have to wait for the dead batteries to finish charging before you can use that electrical device again, then add a few extras here for your calculations. I do not use rechargeable batteries in any of my son’s toys that may disappear as I don’t want to waste my rechargeable batteries. I usually use the cheapest disposable batteries I can find for those toys as they most likely will only get 1 use anyways. So, I need 24 rechargeable batteries which costs $56.97.

Cost of Charger

I also need to add in the cost of the charger which is $14.99 for a charger that can recharge 4 AA or 4 AAA batteries at a time.

Cost to Charge Rechargeable Batteries

Next we need to factor in the cost of electricity to charge each of these NiMH rechargeable batteries. We need to take the cost to charge each battery * the amount of charges we can do on 24 Ni-MH rechargeable batteries. So first the cost of charging each battery cell for each cycle = 9.5 watts * 4.25 hours / 1,000 kW * $0.13 per kWh / 4 cells * 4,800 charge cycles which calculates to $6.2985 to charge these 24 NiMH batteries 4,800 times!

Total Costs of Rechargeable Batteries

Our total costs for buying the AA NiMH batteries ($56.97), buying a battery charger ($14.99), electricity for charging the NiMH batteries 4,800 times ($6.2985), is $78.2585!

Battery Capacities

We also need to know how much battery capacity we have with these NiMH batteries, so we know how many alkaline batteries we need to be equal to them. To calculate this we will take the capacity of each NiMH battery (2,400mAh) and multiply it by the amount of charge cycles we can get from the total charge cycles (24 batteries * 200 charge cycles) which will be 2,400 mAh * 4,800 charge cycles = 11,520,000 total mAh.

Amount of Disposable Batteries Needed to Equal Rechargeable Batteries

Now we know how much the NiMH batteries cost and their total capacity over their lifetime, we need to find out how many alkaline batteries we need and how much the disposable batteries will cost. To get this we need to divide the capacity of each alkaline battery by the total capacity of the NiMH batteries. 11,520,000 mAh / 2,600 mAh of each disposable battery, which means we need 4,430.769231 disposable batteries to equal the same total capacity of the 24 NiMH rechargeable batteries. I know we can’t really have part of a battery, but I’m going to use this number anyway for exact calculation.

Total Cost of Disposable Batteries

Now for the grand total, we need to see how much money these 4,430.769231 alkaline disposable batteries will cost. So we will multiply the number of batteries needed by the cost of each battery; $0.2602083333 * 4,430.769231 = $1,152.923077

Price Comparison of Batteries

As you can see the total cost of NiMH rechargeable batteries is $78.2585 for 11,520,000 mAh worth of battery power is a lot cheaper than the total cost of alkaline disposable batteries which is $1,152.923077 for the same amount of mAh.

Calculation Totals

	NiMH Rechargeable Batteries	Alkaline Disposable Batteries
Amount of Batteries Used:	24	4,430.769231
Total Capacity:	11,520,000 mAh	11,520,000 mAh
Total Costs:	$78.2585	$1,152.923077