I don't think any engineer discounts the potential for energy harvesting to power low energy nodes and I think for certain consumer devices, i.e. remote controls, it coud make sense.
I know your company is obviously heavily invested in the technology and to that end, the implementation details may seem simple to you, however, what is missing in the general knowledge, and in your article, is just how much energy can be collected in a typical environment:
- Realistically how much energy will a solar cell capture if partially shielded in an office environment
- How much energy can one collect from a vibration harvester and in what environments. What is the worst case?
- How much differential to I realistically need for a peltier device and what sort of energy/power output can I get
First and foremost, products must work. Batteries are known entities. Their characteristics are very well known and repeatable under all installation conditions. Where there are failures, the causes are usually easy to debug.
Energy harvesting presents a whole range of possibilities and challenges.
May I suggest a follow up article that discusses those challenges, discusses real world power/energy capabilities of energy harvesting technologies, implementation costs, etc. That is what is required for engineering to propose to marketing new solutions and for CTOs to put their butt on the line.
This is a great article about an important subject. Energy harvesting is indeed a viable alternative to batteries in many low-power applications. It would be nice to know how much current these systems can supply, and how much current it takes to run some of the ultra-low-power applications. Just as important, what are some of the applications that can't use energy harvesting as a power source?
Having worked 7 years in Duracell logic suggests that adaptation of the assembly tooling can be used to dismantle used cells recovering all parts for recycling. It's done for lead acid batteries and can also be done for cylindrical cells at the very least....prismatics are a bit trickier but we're working on it.
Charles, the biggest barrier to battery recycling is not how much of it can be recycled, but rather getting those dead batteries back to any recycling location. Dead batteries are not only a very low value item, they are also often a bit corrosive and somewhat toxic. The logistical challenges of collecting all of those low-value toxic and corrosive cells will not be a small task by any definition. So there is the real challenge. And besides all of that, it is less convenient to dump the cells in a battery recycling bin than in the closest trash bin.
Thanks for a great article on a very timely subject. Non-recycled batteries are a real problem in landfills because of their toxicity. As William points out, battery recycling can be problematic. OTOH, getting used to recycling anything is a matter of habit. We put used batteries in a plastic bag on top of the recycling bin and they get picked up every week curbside.
Excellent article Jim. I agree completely that now is the time to accelerate investigations relative to energy harvesting and push the technology forward in an ongoing fashion. I stand to be corrected but, feel that without Federal and state energy policies, attempts with this undertaking will be fragmented. We all know this will not happen in a judicious manner and the time table will be left up to who get elected next. The work will be left solely up to the private companies dealing with the technology. I am for very limited government so; overall guidelines should and must be accomplished by industry initiatives and the developments by industry standards and policies. For some unknown reason, the FED is always in "catch-up" mode with private concerns doing all of the "heavy lifting".
As long as batteries are dirt cheap they will be partially used in vast quantities and thrown out. Look how many cheap toys are sold with cheap batteries installed, and are often thrown out before the battery is exhausted. There will never be an incentive to switch to alternatives when AA batteries are bought from the source, in bulk, at $0.16 each (or less).
Not so cheap for me. If you have many sensors scattered in your house which needs to be replaced usually once a year then this task is a real burden. It easily takes few hours yearly and my hourly rate is much higer than $0.16. For me, when I see sensor battery powered I look elsewere. Batteries put a real obstacle on automation scalibility.
It is easy to design sensors that can work for 5 years or more on a couple of AA (or even AAA) batteries. Most of us don't really have that many sensors in the house, and much of our battery powered equipment is "asleep" 99% of the day. In many cases, a set of batteries will last the lifetime of the product, as a)circuits can be designed for very very low power and b)the lifecycle of most electronic gadgets doesn't exceed 7 years (usually less).
can you design a radio remote controll which will last 5 year or more? Here I have example of EnOcean in action which replaces universal remote from Bose (havey and powered by 4 AA batteries which I must replace 2 times a year) -- EnOcean does not need any batteries
I can, we did, and we sell the product. Actually it uses a 1/2AA lithium thionyl chloride cell, but thats only because we needed 3.6V and not 3V. We could do it on AA's too. According to our calculations, the remote control would be in use for about 10 hours over the product lifetime, at 20mA thats well within the capacity of the battery. Sleep mode is 2uA. (In practice, most users lose the remote during the first 2 years of ownership). If you want to see the product, look up Ultramax robot. Your name is very common in a certain country, and thats where these products are made.
So you are sugesting that one uses the home cinema remote as frequently as the swimming pool remote? Well... homecinema does not work autonomously and at least in my home has the biggest interaction with users through the remote. IMHO, 10 hours of operation time during the lifetime is way too low. And forget 3.6V expensive batteries, they are 10 times more expensive than AA. It seem for me that your 'cheap' sounds very expensive too me.
I'm suggesting that for every hour of home entertainment use, the remote spends 2 seconds transmission time changing channels, and 5 seconds transmission time changing volume. Each key press translates to about 50msec burst data transmission. For the range required inside the home output power is very low, so less than 10mA is required.
If the batteries are also required to drive a real-time-clock and display, well, thats just a design feature. ISM transmitters can work down to 2.0V, and uPs can work to 2.7V, so 2 AAAs have enough voltage and amp hours to keep you going until you lose the remote behind the sofa cushions.
My own Yamaha AV receiver is 2.5 years old and still has the original manufacturers batteries in the remote.
Jim this is really an interesting post , Most of the batteries consist of Cadmium, zinc, lead , mercury copper and so on all these chemicals are harmfull to humans and to enviornment they cant be thrown like that only suitable place should be find to dispose these batteries instead of disposing batteries it is better to recycle them because all these chemicals are very harmfull cadmium can easliy be absorbed by the roots of the plants and it will be accumulated in vegetables and fruits eaten by us results in lack of different things and minerals.
According to me its great that there are alternatives of batteries but they cant be complety removed instead of harvesting energy and using /inventing rechargable batteries these batteries will still be in use .One should not through these batteries any where because they can be harmfull instead they should be recycled . Recycling of batteries results in income generation, reduction in pollution , saves energy and so on .
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