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EnOcean Wireless Sensors Don't Need Batteries (Video)
'The EnOcean technology is an energy harvesting wireless technology used primarily in building automation systems; but is also applied to other applications in industry, transportation, logistics and smart homes,' says Wikipedia. There's also a Siemans spinoff company called EnOcean, and today's video is an interview with its president, Jim O'Callaghan. But EnOcean technology is the real star here. The idea is that energy-efficient sensors can be powered by energy harvesting, i.e. drawing energy from their surroundings, including such low-level sources as light, temperature changes, and pressure, which can be the pressure of your finger on a switch or even changes in barometric pressure. The EnOcean Alliance has a professionally-produced video that describes their technology and notes that self-powered wireless sensors not only save energy but save miles of wire between sensor nodes and controllers, which means it's possible to install more sensors sensing more parameters than in the past. (Alternate Video Link)
its 2015 dudes.
ITYM Siemens
Not all energy harvesting products are scams.
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This device doesn't use radio waves to power itself. It derives energy from solar (proven, simple), mechanical motion generators (proven, simple), thermal difference (proven, simple).
Deriving energy from radio waves is very possible, Tesla demonstrated it himself. It is also wildly inefficient unless the energy is directed for that purpose. Thus why iFind was probably a scam, since it required more than the most minute amount of power possible. It would be a complex problem to harvest enough to do much of value, whereas solar, motion, and thermal derived electrical energy are so simple and plentiful you can do all three in your home right now AND generate enough power to do something worthwhile (Solar calculator? wind up or shake flashlight? Reverse your car cooler 'fridge'?)
First you're drawing energy from your surroundings, including such low-level sources as light, temperature changes and the next thing you know, you're sucking the energy out of a Star Ship's Warp Coils.
Slippery Slope if I ever saw one.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
It can construct space! awesome!
The Hue lighting PoC was pretty lame, not a lot of use cases there. I'd rather just use the thing that is always in my pocket (and has a battery) . Nothing else seemed very close to being ready for market. Solar is obviously the most common "ambient" power source. That booth just looks very fluffy to me.
So I can power the sensors for my smart home that doesn't need switches, by the pressure of my finger on a switch? I'll take a dozen!
I have a toll transponder sticker attached to the inside of my windshield and it doesn't have a battery. It's powered by the transmission that the toll gantry sends to my device. So I'm pretty sure powered by RF is possible.
Long signatures suck.
Strawmen much? Did you, like, actually read that thread?
That thread has multiple links to actual, working RF harvesting powered devices. They are bigger than a credit card, possibly with external 3-4" antenna, require a dedicated high power transmitter to feed them and even then only intermittently active.
Totally-not-scammers promised an inch sized tag powered purely by background radiation with incredible search radius and active tags.
I live in my parents' cold, dark basement you insensitive clods!
As usual the devil is in the details. Harvesting enough energy from the environment to run a very low power IC in short bursts to do simple sensor measurements? Completely feasible. Charging your cellphone from ambient radio waves? Complete bullcrap.
I read the internet for the articles.
Why does Slashdot video still require Flash?
It can construct space! awesome!
I thought we called those bombs?
I thought powered by RF was impossible and a scam?
First part: Incorrect. Powering something by RF is very much possible. Just look at crystal radios - usable amounts of sound from a device lacking any batteries.
Second part: Correct. That particular instance would have much larger power needs with less area for gathering the power.
Why was that a scam and this is not?
1. They specify low power sensors, not transmitters.
2. They specify a number of different methods to gain power, not just RF.
3. Siemans spinoff indicates access to real engineers and technology.
In this case the vagueness of the claims helps as well. When you start getting specific we can break out the slide rules and do 'rule of thumb' analysis to make sure you're not claiming to be able to break the laws of thermodynamics.
I don't read AC A human right
If you had actually bothered to watch the video, or read the transcript, you'd know that EnOcean is not using RF harvesting to power any of their devices. They are using mechanical, solar, and thermoelectric energy harvesting techniques to power ultra-low power sensors, and to generate RF signals to control other powered appliances (e.g. desk lamps). They are using clever engineering, but they are not making any claims that violate the laws of physics.
iFind was a scam. There was no way that a device that size could harvest, store, and utilize RF energy at the levels claimed by them. Not to mention that the so-called "inventor", supposedly with multiple advanced degrees in engineering and medicine, had absolutely no presence or history on the web.
And Slashdot didn't "kill" iFind. Kickstarter killed it, after performing a little due diligence and realizing that something was fishy with WeTag. But if Slashdot helped pushed Kickstarter into checking into the background of WeTag's principals, then so much the better.
Energy harvesting from ambient RF does work, but to capture significant amounts of energy requires lots of area (e.g. an antenna or large pickup coil), or to have RF energy beamed directly at the device. At no time does EnOcean claim to be using RF harvesting to power their devices; they are only using ultra-low power RF radio bursts for short-range communication.
Why was that a scam and this is not?
Because that they have working products and aren't grubbing around for the great unwashed's loose change on Kickstarter, for a start.
That past Slashdot story was about the many questions that were already being floated about iFind. That's why it was a story in the first place.
So, really, your question is a bit like asking why a story about Steve Jobs kicking a puppy results in more negative comments about the subject than one about Bill Gates single handedly saving 20 children from an orphanage fire.
Incidentally I think you credit Slashdot with way too much influence if you think it can bring down a startup in a couple of days. Those guys were already on their way out (this, again, being what the story was more or less about).
systemd is Roko's Basilisk.
A small, infrequent burst of information over a short range can be done from collected RF, while a continuous long range signal is pretty much not going to happen.
...Well..
TECHNICALLY, you only need to gather enough power to overcome the internal resistance of the battery to "charge your cellphone from ambient radio waves". There's lots of use cases that this is possible (though you'd need to be pretty damn close to a transmitter!) and the idea that you're going to be able to do it in any "reasonable" timeframe IS bullcrap.
Charging from background in the average city is possible, there's lots of energy around at any given moment. Charging a battery might take a few weeks (or months!), but it is do-able. Doing a rotation where you use a different battery EVERY DAY for months would be far from feasible for most people presently. Background is generally measured in microwatts, so you're really looking at low power here!
Development markets would see the most benefit from something like this, yet would be furthest from the power density to make use of it.
Imagine ultra low power devices, (IE we're talking 2-3mW average standby) with 15-20 day standby times from ~1000mWh batteries that twice a month you go swap the battery out into a pool of say ~20 batteries that are always on rotation on the chargers. ~300 days of charge time on the furthest battery at a few hundred microwatts (I'm going to pick 250uW @ 900MHz as it's present here where I live, the value will vary wildly from place to place and based on everything from antenna position to cable loss to connector oxidization! Average background in a dense populated area that has built-up infrastructure, depending on frequency range and LOS to the various transmission sources may be different elsewhere, but it's pretty consistent with a cheap dipole near a window here) you're looking at ~166 days + charger inefficiency. Given battery chargers are generally pretty high efficiency these days, say 85% you're looking at ~191ish days to charge each cell.
There are plenty of devices powered by ambient RF, including everything from crystal radios to things that include IC and are capable of communicating back. However, even people who have experience building such things and knowing RF powered devices are possible were speaking out against that particular case. The usage of bluetooth they claimed was not appropriate to the power available, and some of the numbers they gave for power levels were just flat out unrealistic. I never followed up with it myself to find out if they were lying or if they were just doing a horrible job of measurements and/or communication. It would suck to not be a scam, but just be people who made a mistake, or were promising a feature beyond what they thought they were promising.
As with a lot of things, "efficient" scams and unintentional deceits involve some element of truth, and try to point at other similar ideas that work hoping you won't notice the details that matter. An extreme example was an "over unity" advocate I came across that would defend his device by claiming that "switching power supplies work and are really efficient," which is true, but doesn't mean that his switching power supply was more than 100% efficient, nor addressed the fact you could see right from his plots he simply failed to understand how to calculate power for AC. Or an advertisement for a fuel additive with claimed mileage that exceeded 100% efficent use of energy density of gasoline, but that doesn't mean there aren't fuel additives that can make some improvement to efficiency in specific cases. It is just like those that claim "They laughed at Newton and Galileo... etc."
... but it had me thinking the product was maritime sensors that harvest energy from the oceans.
There's indeed a number of potential energy sources in the ocean, that is sun, wind, waves and water constantly pushing you in various directions or even living and dead organic matter.
I believe we badly need thousands upon thousands of sensors floating in the oceans, because they're poorly known and we have many severe changes going on (collapse and blooms of species, warming of layers, acidification), we need to understand about the sixth extinction and about dangers and opportunities.
As usual the devil is in the details. Harvesting enough energy from the environment to run a very low power IC in short bursts to do simple sensor measurements? Completely feasible. Charging your cellphone from ambient radio waves? Complete bullcrap.
As usual, the ability of the Slashdot community to even bother clicking on the god damned link is thwarted by their lazyness. It doesn't charge your cellphone. Where the hell did you get that?
It was a tag that hung on your keys, charged by RF that listened for a specific radio signal (like your garage door opener) When it received said signal it would beep. That's it. There's no physical reason that wasn't possible. The company could have still been a scam, but the device itself was possible.
1. They specify low power sensors, not transmitters.
Whoever said iFind was a transmitter? For all we know it "Beeped' when lost. In fact, I assumed that's how it would work. Why the hell would it transmit? Even if it did transmit, the most power it could transmit by law would be 1 watt. Why is that unfeasible?
2. They specify a number of different methods to gain power, not just RF.
And that has what to do with the price of tea in china? So only 1 of there several methods of charging is a scam?
3. Siemans spinoff indicates access to real engineers and technology.
right... because they used to work at Siemans, they are fully backed by that companies brand name? lol
Violates the laws of physics does it?
http://www.mouser.com/new/powe...
Look at it. Read the damned data sheet: http://www.mouser.com/ds/2/329...
You'd better let the world know one of the largest Electronics parts suppliers in the world is scamming them then. Because that's exactly what that IC does. 50ma output to! I doubt it gets that continuously, but carried around in close proximity to your phone and computer? Over a period of months? You're damned strait that'd charge it.
FYI that RF harvester is specifically designed to power sensors like what's described in this article. You're supposed to hook it up to a battery and a sensor like this and power that sensor to wireless transmit its readings.
Why was that a scam and this is not?
Because that they have working products and aren't grubbing around for the great unwashed's loose change on Kickstarter, for a start.
That past Slashdot story was about the many questions that were already being floated about iFind. That's why it was a story in the first place.
So, really, your question is a bit like asking why a story about Steve Jobs kicking a puppy results in more negative comments about the subject than one about Bill Gates single handedly saving 20 children from an orphanage fire.
Incidentally I think you credit Slashdot with way too much influence if you think it can bring down a startup in a couple of days. Those guys were already on their way out (this, again, being what the story was more or less about).
But read the thread... no one discussed the dudes fishyness. It was all a lot of bloated "I know about electronics and..." nonsense saying it was physically impossible. It's not. You can buy a dozen sensors just like the ones in this article that are powered by ambient RF or light, or whatever. It's an industry that's existed for years now. Were they a scam? I have no idea, but if it were a scam it had nothing to do with the physical impossibility of the device they designed.
Whoever said iFind was a transmitter? For all we know it "Beeped' when lost. In fact, I assumed that's how it would work. Why the hell would it transmit? Even if it did transmit, the most power it could transmit by law would be 1 watt. Why is that unfeasible?
1. The website trying to sell it.
2. In order for a locating device(your cellphone) to find it.
3. 1 watt is a HUGE amount of power for these sorts of devices. Normally you're looking at milliwatts
And that has what to do with the price of tea in china? So only 1 of there several methods of charging is a scam?
This article is about a company that's releasing a number of different sensors, each presumably mated with a charging system designed for it's deployment zone and power needs. Why different sources of charging(well, powering)? Because they'll be deployed in different environments. iFind had a specific purpose and claim for what it would be powered by, as well as dimensions for the packaging. If EnOcean came out with a package that was, for example 'sonar buoy, solar powered, 1 meter diameter', we could analyze that and realize that ~.7 square meters of solar panel is quite a bit of power. 'passive sonar buoy, anchored, tidal powered' would still make sense, though I'd think they'd have to be very clever to get the power demands that low.
right... because they used to work at Siemans, they are fully backed by that companies brand name? lol
Keep loling at that strawman. That it's a spinoff means that it's a serious product, if probably somewhat risky. It's much less likely to be a hoax than random people off the internet. It has history.
I don't read AC A human right
Did you even look at the damn link, or were you too lazy and expecting others to read through it? I remember that story being posted, but did double check it was the same one with the posts I thought were there. There are posts with specific numbers, working out in detail the power requirements. At the time, the company made specific claims about their device's size, ability to communicate over Bluetooth and even posted figures with claims on how much power they could generate. It didn't add up, the Bluetooth modes and ranges they were claiming to use was not within the reasonable power budget, the power they claimed to receive was unrealistic, and they were advertising more than just making it beep but keep track whenever it entered or left range. Some of those things are possible, but RF powered devices use other protocols than Bluetooth typically, which are purpose built for such low power uses. While the device you remember through rose tinted glasses is possible, not how and with the numbers they claimed. But I guess I shouldn't expect people to click a link and read it...
Powerharvester stuff is designed for use with a base station that transmits 1-3 W of power, and has a maximum range listed as 40-50 ft for such a base station. That is not designed for use with ambient RF.
There are other systems for collecting ambient RF, but their power is considerably less without a large antenna. Even Powerharvester supplies ~6" antennas for use with their dev kits.
A friend once brought me a schematic to a circuit he read could take in 1 W of power from a battery, and output 2 W of power to a motor. I told him it looked like just a switching power supply, and it would not physically be capable of outputting more power than goes in to it. He then went on a rant about how stupid it was to say switching power supplies are impossible and how common they are used in electronics everywhere...
Sounds really familiar. Just because someone says some specific numbers are impossible to achieve is not the same as saying that the principle is impossible in general.
It's an industry that's existed for years now.
It is an industry I work in. Even when stating that and reminding people that ambient RF harvesting can work in certain cases despite also finding that the numbers given by iFind were BS (scam, mistake, ignorance, whatever), others had to insist that I was claiming RF harvesting was impossible under all cases and remind me that the industry I work in existed. For whatever reason, there is a really pervasive strawman that you and others keep seeing in the original arguments about iFind.
You lament how people won't read what you link, yet you won't even read what you link, or for that matter, replies to when you tried to post a link to the exact same product line before. The datasheet you link to is for a series of chips powered by a dedicated transmitter and using much larger antennas than iFind for that power.
It seems from looking at the actual link given, that the claim "powered by RF was impossible and a scam" is a strawman. But not just any strawman, a strawman that Charliemopps constructed and tried to fight in the comments of the very story he links. Despite the refutations and reminders of it being a strawman argument in the original story, it looks like he has come here to beat a straw horse and troll up a bunch more comments attempting to remind him that "Either everything claiming to do X is fully possible or they are all impossible" is a false dichotomy.
In fact, I assumed that's how it would work.
And what happens when you assume things, and then try bitching about others not making sense? Shouldn't that be a hint?
iFind advertised a mode that your phone would indicate when a tag left outside a certain, potentially large range, and at one point advertised another mode that would indicate proximity to the phone. These both required communication from the tag to the phone, and at reasonable rates so that you would notice when it happened (the advertised claims about how frequently it would contact the phone decreased at some point). The link you already provided had plenty of people giving the math behind why even a minimal Bluetooth packet once every 10-30 seconds would exceed the power that something that size could collect from ambient RF. Hitting the legal 1 W limit was not an issue if you can't reach the max. spec'ed Bluetooth power of 100 mW needed for the 100+ ft range they advertised.
I have an 80+ year old Atmos torsion pendulum mantel clock. It never needs winding, it harvests energy from atmospheric pressure changes (or temperature changes). Air pressure in a sealed can will run the clock for a week on just a 2F degree swing in ambient temperature.
You have to do more than overcome the internal resistance of the battery, you also have to supply energy faster than the natural discharge rate of the battery.
I read the internet for the articles.
Stuete has been making wireless EnOcean limit switches for years, so what is new about this story other than an obvious Siemens marketing ploy??