Plant a couple trees and over the next decade you'll sink more carbon than you'll ever release with this thing (not considering the carbon emitted when the thing was built and shipped to you...)
When we get our fuel from trees, we've created space for new trees to grow. In contrast, when our fuel is coal, gas or oil, eventually we run of of places to plant trees (or we run out of the whatever is the scarcest nutrient for the trees).
This is the basis for the claim that burning trees is friendlier to the environment than burning fossil fuels is.
I am NOT pushing the claim, just pointing out that you have not yet successfully refuted the claim.
Ok, continue the chase through cause and effect. That stove consumes many precious and rare components (thermocouples, conductors, computer chips!) Its manufacture totally blows any comforting thoughts about carbon footprint savings.
"Green" arguments like this product are marketing and 1st-world-consumer foolishness. Build a campfire and cook in an iron pot - that might save some carbon. This thing? No.
The problem with arguments like this, is that it only takes into account costs for today's industrial infrastructure. If everyone thought like this, there would be less innovation. (No domestic solar panels, for one thing.)
That said, there are probably smaller carbon footprint items that will accomplish the same thing. Bulk D Cells, some D-cell holders and a USB charger would be what I'd use for extended emergency preparedness.
Most serious backpackers aren't concerned with nursing portable electronics with a low efficiency TEC. People who actually need to use electronics in remote locations bring a LiPo battery and a solar charger.
This is a camp stove. You cook things on it. It has a fan to provide a very efficient, very clean burn.
It happens to have a charger on it as a side effect of being a fan driven burner. I guarantee that "getting power for free while cooking breakfast" is dramatically more efficient than a solar panel.
Add that hiking I'm going to cook multiple times. Number of times I'm in open sunlight, at a fixed location for a period of time -- approximately zero.
Not sure what you have against this, but it seems to be founded in the notion that you think this is a wood-powered USB charger, when it's a camp stove that also provides USB charging.
Actually doing the arithmetic and demonstrating that an alcohol stove plus a standard-sized container of fuel weighs more and doesn't give you the USB charging capability gets me a -1?
Nice.
We won't even go into the fact that some people go backpacking in places where fuel has to be flown in (which, coincidentally, also tend to be the places where having a GPS or satellite phone can save your life).
Alcohol stoves are nice and light but (along with any stove without an off valve) are technically illegal in most national forests and have started forest fires. If you spill one it is almost a guaranteed forest fire as you have invisible flame everywhere.
Personally I'm a fan of isobutane models after years of fighting with white gas models.
What are you talking about? I have a solo stove (same idea but without the USB gimmick). These things burn twigs that you find the the forest floor. An entirely carbon neutral and renewable resource. They are the total opposite of burning fossil fuels, that is why we use them.
Right, putting that carbon back into the atmosphere instead on the forest floor where it started is carbon neutral. Just because it is "part o the carbon cycle" doesn't make it neutral.
What happens to the wood you don't burn? It decomposes letting CO2 into the atmosphere. Fossil fuels release carbon captured millions of years ago, over millions of years, in a very short time. That's the difference.
Wood is worse than other fuels by most accounts, but I guess if you were planning to build a fire for warmth anyway it's not so bad.
Thermoelectric generators are something like 200yrs old though and this isn't even the first hiking oriented variant (http://www.powerpractical.com/ - not obvious on the front page, but it also works fine with a wood fire). Historically I think hikers considered this a non-issue because of better battery life and/or keeping your phone off except in emergencies.
It's a little ironic that people are staying tied to their smart-phone even during long camping trips. These really aren't good for much else because they only keep a good heat difference for a short time and have to be used with a battery.
Wood is carbon neutral (trees are, of course, very efficient solar energy plants), and backpackers burning scrub branches are not diminishing nature. Further the fan leads to an extremely clean burn, which was the original intention of these various designs.
Quite a few people throughout this thread seem to be under the assumption that the intention of this device is purely as a charger. It is instead a camp stove that incidentally can charge as a side effect of having a powered fan. Instead of a propane stove or the like, the idea is that this makes it easy to use small branches to cook breakfast or whatever.
The biggest criticism I've heard of this device is that it's a pain and highly inconvenient to constantly feed it twigs when you try to heat anything of consequence (e.g. pot of water).
I don't know where you're getting that information. Burning wood produces significantly more CO2 than coal or oil regardless of your air flow; not to mention CO, volatile organic compounds, and nitrogen oxides. If you've ever had the displeasure of being within a few miles of a forest fire, it's really rough on the lungs.
You can argue that by growing the tree specifically to burn and then being careful how you harvest it, the wood burning ends up being carbon neutral. That's obviously not the case here, and it doesn't scale in general.
Worldwide, and across all scientific realms, burning wood is considered carbon neutral. This is not an "argument", it is actual reality -- the carbon released when you burn wood is identical to the carbon captured to form the same, and which will be captured in its place. The branches that fall to the ground will often become, in a relatively short timeframe, CH4, which is much worse than CO2.
Add that this is relative to coal or oil or natural gas that have been carbon stored underground for millions of years.
This is not up for debate. It is not open for you to argue whether it "scales". It is the reality of the planet that we live on. Your opinion on it is utterly irrelevant.
And it's actually humorous that you mention forest fires given that removing the brush that camp stoves like this burns helps prevent forest fires, not to mention decomposition methane.
As to being rough on the lungs, the whole point of this whole initiative is clean burning the wood, eliminating the vast majority of particulate that is the result of an incomplete burn. I suspect you really don't care about the actual facts though, but just for anyone else coming along.
> Worldwide, and across all scientific realms, burning wood is considered carbon neutral, right?
Absolutely not. For wood burning to be carbon neutral, you have to replace the wood and produce exactly zero CO2 during harvesting and transportation. Even if we gave your picking up twigs example a good 50yrs to cycle, you're removing fertilizer that would otherwise help the growth of current/new trees. There's a reason we put restrictions on wood burning and overall traffic in a lot of forest areas; it reduces the forestation.
> This is relative to coal or oil or natural gas that have been carbon stored underground for millions of years.
The length of the cycle doesn't make a difference because we're growing energy production exponentially and seeing consistent global deforestation (thus the scaling problem). That carbon from your stove might get replaced in 10-50 years.... if not for the environment suffering immediate effects that propagate.
> And it's actually humorous that you mention forest fires given that removing the brush that camp stoves like this burns helps prevent forest fires
Not in any significant way. As far as we know, forest fires are caused by weather patterns, forest life-cycles, insect life-cycles, ect. Clearing brush is a stop-gap fire fighters use to protect homes.
> As to being rough on the lungs, the whole point of this whole initiative is clean burning the wood, eliminating the vast majority of particulate that is the result of an incomplete burn.
The vast majority? I doubt either of us is going to do a study on this particular stove, but given that Biomass power facilities still produce large amounts of particulates, I'm pretty sure the little self-charging fan doesn't solve the problem.
> I suspect you really don't care about the actual facts though, but just for anyone else coming along.
I'm doing my best not to be confrontational, but your only "fact" is the misapplied notion that trees can only release carbon that they've previously absorbed. Every study I've read on using biomass for power generation has concluded that their only "environmental" advantage is that the fuel is easier to renew.
"you're removing fertilizer that would otherwise help the growth of current/new trees"
There is astonishingly little fertilizer potential of fallen wood (and the little there is remains in the ash). In parks it is controlled primarily because it acts as an ecosystem for levels of the pyramid, so overharvesting in dense areas is a problem.
"The vast majority? I doubt either of us is going to do a study on this particular stove"
"carbon monoxide and particulate matter emissions reductions of 91% and 94%, respectively, while lowering fuel usage by 42%"
I'm doing my best not to be confrontational, but your only "fact" is the misapplied notion that trees can only release carbon that they've previously absorbed.
Well, it's good that you're not being confrontational, especially when you are speaking such utter nonsense, with a complete lack of any facts whatsoever. We are talking about a stove picking up scrap wood, which is, by every scientific definition on this great Earth, carbon neutral.
> There is astonishingly little fertilizer potential of fallen wood.
What possible reason could you have for thinking this? Pointing out that wood has been used in mulches and fertilizes for ... millenia ought to suffice, but since you seemed vexed by my lack of "facts". Here are some studies showing increased growth as a result of wood chip use -
From your link, "Standard water boil tests of early BioLite prototypes demonstrated carbon monoxide and particulate matter emissions reductions of 91% and 94%, respectively, while lowering fuel usage by 42% relative to a three stone fire"
So... not useful figures because they're from a prototype and not compared to another stove. I also wouldn't call that a vast majority in context since the relevant comparison is to a gas or alcohol fueled stove.
> Well, it's good that you're not being confrontational, especially when you are speaking such utter nonsense, with a complete lack of any facts whatsoever.
I was trying not to insult you by googling references for well-known results. That was evidently folly on my part -
You are incredible. Do you realize that nothing, at all, that you have referenced supports your arguments at all. Yes, you know how to use Google: Congratulations, you have achieved a primary school level of achievement. Yet you remain blissfully and completely unaware of any contextual relevance of what you are linking. "This looks related...".
Further, the reduction was specifically about this method of burning wood versus your comical, hysterical claims. Wood burning creates soot and particulate when it is oxygen starved. The solution is to have a fan to feed it a steady supply. This is not rocket science.
Do you understand that we are talking about people burning twigs that have fallen to the ground? Do you understand how incredibly specious it is to talk about industry biomass production facilities.
I have never seen someone so profoundly wrong so steadfastly try to stick to an absolutely, utterly nonsensical opinion. You having NOTHING interesting to say on this. And filling your posts full of links saying nothing of the sort borders on pathological.
> Yet you remain blissfully and completely unaware of any contextual relevance of what you are linking.
They're all about the complex carbon footprint of burning wood. Perhaps you might try explaining why they're unrelated.
> Wood burning creates soot and particulate when it is oxygen starved. The solution is to have a fan to feed it a steady supply.
Wood doesn't completely burn... when it doesn't completely burn. There are a lot of factors and a small fan doesn't solve all of them (this should be self-evident or the reduction would be 100%). Obviously, the comparison has to be made to stoves/generators using other fuels (ie gas/alcohol/petrol if you really want) because that was the original comparison - wood to other fuels, not wood burning stove to other inefficient wood burning method. Please refer back to the original post.
> Do you understand that we are talking about people burning twigs that have fallen to the ground? Do you understand how incredibly specious it is to talk about industry biomass production facilities.
If you'd bothered to read anything (the first article and associated reports go into a lot of depth on this), you'd see that burning dead branches sparingly (and correctly - this stove still has a lot of pollution relative to industrial methods) is one of the better methods. However, you have to be very careful about the type of wood you burn, the condition it's in when you burn it, the way you burn it, how much of it you remove, ect.
It's very complicated and in general it's done less efficiently than alternative fuels atm. The "ZOMG BURNING WOOD IS INHERENTLY CARBON NEUTRAL" thing is short-sighted and has been outdated for a good two decades now.
Do you want "facts" or not? Because you're not reading any of the ones I reference.
On the contrary. Burning (current) biomass is essentially carbon neutral. It's burning fossil fuel that causes the carbon dioxide level in the atmosphere to increase.
This has looked cool, ever since I saw it announced, a peltier in a stove - how awesome! i just can bring myself to pony up the cash as I fear it would fall short of my expectations. kind of like this real world test. http://indefinitelywild.gizmodo.com/adventure-tested-biolite...
good point, should have said TE or thermoelectric, i just learned of the device as a peltier junction even though it has 3 different names depending on the mode. at work we call it a TEC based on how we use it, but the best most generic name is TE.
You have to constantly feed this thing fuel in order to 'charge' anything. It's an overpriced, overweight gimmick. You'd be better off bringing a stack of extra batteries than this poor excuse for a stove/charger.
I'm currently on the Appalachian Trail and have seen a few of these... They're neat, but dont work very well. Maybe for a weekend trip. Not for serious distance hikers.
I could see this being handy on larger group camps.
I'm a Scout leader and for a weekend camp will take a battery pack that will keep all our leader's phones charged for the weekend, but if it were any longer or wanted to give the neighbouring camps a charge, would need something solar or fuelled. From what I've seen of the solar stuff out there, most can't keep up with constant charging.
All the reviews I have seen seem to agree that it takes around 4 hours to for the BioLite fully charge an iPhone. For the same amount of weight you could carry 3 Anker 12,000 mAh batteries, which I believe would provide on the order of 15 charges, at a cost of $150.
Unless you have scouts tending the BioLite constantly, I think it is definitely not a solution for groups.
Well, it only boils water. For that purpose some competitors would be:
- Backcountry Boiler, which is also wood-fueled and 1/4 the weight.
- Jetboil Sol, half the weight including fuel canister. canister good for 20+ boils
- alcohol or esbit burner + titanium cup and fuel - less than 1/3 the weight including fuel
The only scenario I can think of where the BioLite makes sense is if you have no access to electricity for weeks at a time. Even then I think solar panels make more sense.
It's primarily a stove, and does a relatively good job at boiling water or cooking food. As a nice bonus for us, we used it to shave some crank time off a hand-crank/USB-chargeable lantern, deep enough in the woods that a solar panel probably wouldn't have done a whole lot.
(FWIW, I generally agree that it's probably not great for serious backpacking, but I had a lot of fun using while camping.)
On the AT up to a few weeks ago. A few hundred miles in a weekend hiker with one of these at a shelter let everyone recharge their devices and they were a modern Prometheus to us. If weight (33 oz + pot + utensil) were not such a crucial consideration to one's happiness when long distance hiking it would definitely be in my pack. It has worked very well for me when testing at home (boils 1 liter of water in ~4 minutes using a handful of wood fuel) and charges devices (subjectively) as fast as my wall outlet.
I plan on winter hiking thru some areas with re-supply locations > 7 days apart and may use the biolite in place of my solar external battery (9.4 oz) since it will also serve for melting snow. I did not cook anything while on the AT (just soylent and mainstay bars) but I anticipate that warm meals will make winter hiking more enjoyable.
We've got one. My wife's used it on a weekend camping trip; I haven't had the opportunity so far, so this is her second-hand report ...
It works as described. However, you need to charge the power module before the first time you use it! The Biolite stove relies on fan assistance, so if there's no juice the stove won't work.
Once it's working, it works fine and charges the power module (via the built-in thermocouple).
The stove is designed to fold down and fit inside the optional kettle, so what superficially looks like a bulky kit is rather less so in practice. However, the stove+kettle combination weighs about 1.1Kg. There are lighter camp stoves out there (until you start adding in gas cylinders).
The optional grill doesn't seem to fold down/store concentrically with anything, so it adds bulk while costing rather more than rival cheap camping grils.
That sounds like a huge design flaw. It should have a hand crank to start moving air over the TEC so it can create enough power to run the fan motor.
It seems kinda wrong to be out in nature, burning wood to charge a device. Why is this better than a small solar panel? A panel wouldn't have the fire danger, could be left out all day and charge its own batteries. Also, the efficiency of a TEC is really low, lower than solar panels by a pretty large margin.
I reviewed one of these a couple years ago for Macworld, and ended up buying one to take on my camping trips.
You don't actually need to charge the power unit in order to use the stove; even if you start with a completely run-down battery, the unit will eventually generate enough electricity to start the fan and achieve maximum efficiency.
Also, it's always seemed to me that the Biolite is designed primarily as a reasonably efficient biomass stove—a role that, in my experience, it fulfills really well, even with wet wood. I've cooked plenty of meals on it, and it's much more convenient to carry around than a propane or white gas stove (as a bonus, you also don't walk around with explosives in your backpack).
The ability to charge devices is a happy byproduct. It's handy when you're cooking up some food and want to power up your phone or GPS receiver. It's probably not as efficient as a solar charges but (a) a solar charger won't cook food, so the Biolite is a convenient multitasker that requires less backpack room, and (b) the solar charger doesn't work at night, when it's cloudy, and so forth.
EDIT: FWIW, I also have a PowerPot, which is mentioned elsewhere in this thread. It's pretty cool, and works well; it's also my preferred charging method when I am not cooking, since I can just fill it with water and leave it on the campfire for as long as I need (the Biolite, on the other hand, needs constant feeding of fuel to continue running).
While it's true that a non satellite phone is never a good panic button, in my experience,
[a] danger doesn't always correlate to distance from civilization.
[b] cell reception can be astoundingly good in the mountains, probably because of clearer lines of sight.
Probably the more significant thing is that it's a self-powered forced-air rocket stove (part of the current generated drives a fan). The self-powering is interesting, but I'm not sure how much it adds or if the forced air just makes up for the energy taken out by the electronics.
The rated output (2-4W @ 5V) seems impressive, but I'm not certain I buy it or at least I'd wonder just how much you need to be feeding the fire. I don't see any mention of a battery pack, but I think if I'm charging expensive and sensitive devices I'd rather charge batteries, then charge my devices with a more stable current. Adding your own battery is going to bump the already-considerable weight (> 2lbs).
They do present a comparison to the "conventional alternative" of an alcohol stove + fuel + solar, but for some reason it seems designed to make the conventional alternative as unappealing as possible (44 oz & > $200 for a stove plus fuel for 2.5hrs of burn time!). Not included are options such as a simpler rocket stove (easy to make) or a SuperCat alcohol stove (cheap & REALLY easy to make) and options to make those more efficient (shrouds, etc. sized for your cookware).
As for charging, there are actually some pretty impressive solar options designed for backpacking - they aren't on-demand like this, but many of them incorporate a battery system and could likely be used on a pack while hiking, so the battery pack is available when you stop, and you can use them in places where you don't really want a fire.
I'd have to call this fashionable, but I'm not sure how practical it really is for most people.
Edit: forgot to mention, the base unit for this is ~$130, and the kettle/carrying case adds another $50 and 1 lb to the whole thing.
So there was a competitor to Biolite (PowerPot) on Shark Tank a couple of months ago, they claimed a patent filed in 2010[1] on the technology, Biolite filed in 2012 [2]
Grepping around the patent database doesn't turn up anything for the Powerpot, or assigned to Power Practical, or invented by Dave Toledo so I'm at a loss to know where they are on that.
That said, the tool, which requires boiling water only so that the correct temperature differential is maintained, seems a bit too specialized for back packing. It raises an interesting question on the weight budget for power though. I am guessing that a white gas fuel cell would be a much better answer from a practical point of view.
Does anyone know how these compare to FlameStower? Their tech looks pretty cool because you can use it with any heat source (campfire, camp stove, etc.), but I don't know how the efficiency stacks up against these standalone devices.
Burning wood releases a lot of carcinogenic microparticles that enter your blood directly from your lungs and is even worse for you than smoking. I'd rather just carry some gas around and use solar power to charge my gadgets.
You're not the intended market. The people likely to be buying this are those who would have had a wood-based camping stove / sat around a campfire anyways.
This gets posted here and there every couple months. Each time someone talks about how it charges things well enough but you do have to keep an eye on the fire and feed it rather constantly, plus it's heavy.
However it seems that few people ever acknowledge that you basically have an at-will generator that you can carry in a pocket--albeit as long as it's a big pocket. So theoretically if you have this and a GPS unit, it's almost impossible to get lost, no matter how long you are out in the wild.
It may seem a bit bulky and there are lighter and more efficient ways to cook on the trail, but for the right sort of traveler, this stove is also bundled with some potentially life saving abilities.
I'm not terribly adventurous in real life, but I think if you are planning on getting that lost a GPS probably isn't the right sort of fallback (I'm thinking a waterproof map and a good understanding of how to get un-lost in the region you are in...).
You ideally need both. A good GPS to tell you where you are, and a good map (and the sense and skill to read it) to tell you how to get somewhere else.
My father once said a GPS is just a device to remind you how lost you are.
In 2008 some friends and I went on adventurous trip through Russia and Kazakhstan. Some of it was through steppe with rough roads/tracks/drivable surfaces that are not on the maps. They were visible on satellite imagery though.
Our navigation "solution" was a laptop and Garmin GPS attached via USB. Laptop would be powered from car battery with power converter.
For software, we were going to use OziExplorer, which could display raster maps, and show current GPS location on them. Ozi maps are simply big raster images and there is limit of how big they can be.
Before the trip I found a tool that can scrape Google Maps satellite imagery and generate Ozi-compatible maps. So I ran it on the parts of Russia and Kazakhstan we expected to visit and got many gigabytes of cached satellite imagery.
During the trip as we moved along, I would use the tool to generate Ozi map for next area we were visiting. I got pretty handy at doing latitude and longitude bounding box calculations "in head" :-)
To give idea of working conditions:
There were various "oh shit" moments along the trip, one of which was when the power converter stopped working (and laptop's battery was empty because its charging circuit got fried earlier, guess because of the unstable power or overheating). GPS was still running on its internal battery so we did know our latitude and longitude and bearing. But our paper maps were not much use. The population density in steppe was so low, we could just drive until we'd run out of gas and water, and not meet anybody. I think we were shorter on water, as we had to use some of it to top up leaky radiators.
Anyway, all ended well when our mechanic-guy found and fixed a simple wiring issue with the power converter, and we got the laptop back on!
To be fair to the point I was making, you had used the GPS and maps to get lost in the first place.
(Which is your group's choice to make; I don't mean to moralize and lecturify, my earlier point was just to push back on the idea that a GPS and thermoelectric stove are safety equipment)
To put this in perspective compared to the new 1.2 V, 3500 mAh NiMH batteries (available for ~$1 each on eBay), let’s say we need 5 of them to go from 6 V to 5 V as they discharge. That’s a total of 17500 mAh (17.5 Ah). 5 V at 4 W is a current of 0.8 A by P = IV, so the batteries could run for just under 17.5/0.8 = 22 hours (slightly longer, since V > 5 which means I < 0.8).
They don’t say how much thermal wattage the stove puts out, but 1000 W electric camp stoves are readily available so I will go with that. 2-4 W of electric power translates to about 2-4% thermocouple efficiency which is pretty good.
I think perhaps in the near future we’ll see some innovations in heat engines like Stirlings which easily reach 50% of Carnot efficiency. They have a reputation for low power to size ratios, but that’s due to lack of compression (easily remedied if anyone, well, tried):
So to boil water at 212 F (100 C or 373 K) at an ambient temperature of 72 F (22 C or 295 K):
Carnot efficiency = (373 - 295)/(373) ~= 21%
So a Stirling engine would achieve 10.5% at the heating surface, or about 2.6 times better than a thermocouple.
However, if we put the Stirling engine within the flame with modern ceramics and, say, graphite lubricant which can go to 842 F (450 C or 723 K), we could run at say 500 F (260 C or 533 K):
Carnot efficiency = (533 - 295)/(533) ~= 45%
So a Stirling engine would achieve 22.5% in the flame, or about 5.6 times better than a thermocouple.
Of course then you are dealing with moving parts and it would probably be unreliable. But the whole engine could be made airtight with the generator enclosed inside, so it might be possible to build one with a service interval of tens of thousands of hours or more.
Also I’m probably being too conservative on Stirling engine efficiency and too optimistic about thermocouple efficiency, so a Stirling engine is probably more like 5 to 10 times more efficient than a thermocouple.
I’ve often wondered if it’s possible to build a solid state device that raises the frequency of infrared radiation to the visible range so that it could be converted to electricity by a high efficiency photovoltaic cell. It can’t be done by concentration alone because the laws of thermodynamics state that concentrators can’t reach a temperature hotter than the source (5300 C for the surface of the sun), although using multiple cells optimized for specific frequency ranges seems promising:
I see that as perhaps one of the great engineering challenges of our time, because low temperature gradient free energy is all around us (orders of magnitude more than we could ever use) but we have no way to gather and concentrate it cheaply. So far this is the most promising method I’ve found for visible light:
High compression sterling engines also tend to be really heavy and bulky since the whole thing ends of needing to be encased in a compressed chamber. They are cool though.
79 comments
[ 2.7 ms ] story [ 158 ms ] threadThis is the basis for the claim that burning trees is friendlier to the environment than burning fossil fuels is.
I am NOT pushing the claim, just pointing out that you have not yet successfully refuted the claim.
"Green" arguments like this product are marketing and 1st-world-consumer foolishness. Build a campfire and cook in an iron pot - that might save some carbon. This thing? No.
That said, there are probably smaller carbon footprint items that will accomplish the same thing. Bulk D Cells, some D-cell holders and a USB charger would be what I'd use for extended emergency preparedness.
This is a camp stove. You cook things on it. It has a fan to provide a very efficient, very clean burn.
It happens to have a charger on it as a side effect of being a fan driven burner. I guarantee that "getting power for free while cooking breakfast" is dramatically more efficient than a solar panel.
Add that hiking I'm going to cook multiple times. Number of times I'm in open sunlight, at a fixed location for a period of time -- approximately zero.
Not sure what you have against this, but it seems to be founded in the notion that you think this is a wood-powered USB charger, when it's a camp stove that also provides USB charging.
You have to buy (and carry!) alcohol.
This is a gimmick for people who can't go camping without their electronic gadgets. It's a bad stove and a bad charger put together.
The Trangia backpacking alcohol stove sold by REI weighs 5.75 ounces.
1 quart of denatured ethanol weighs about 28 ounces (varies slightly depending on denaturant, but not by much).
28 + 5.75 = 33.75 > 33.
Next.
Nice.
We won't even go into the fact that some people go backpacking in places where fuel has to be flown in (which, coincidentally, also tend to be the places where having a GPS or satellite phone can save your life).
Personally I'm a fan of isobutane models after years of fighting with white gas models.
Thermoelectric generators are something like 200yrs old though and this isn't even the first hiking oriented variant (http://www.powerpractical.com/ - not obvious on the front page, but it also works fine with a wood fire). Historically I think hikers considered this a non-issue because of better battery life and/or keeping your phone off except in emergencies.
It's a little ironic that people are staying tied to their smart-phone even during long camping trips. These really aren't good for much else because they only keep a good heat difference for a short time and have to be used with a battery.
Wood is carbon neutral (trees are, of course, very efficient solar energy plants), and backpackers burning scrub branches are not diminishing nature. Further the fan leads to an extremely clean burn, which was the original intention of these various designs.
Quite a few people throughout this thread seem to be under the assumption that the intention of this device is purely as a charger. It is instead a camp stove that incidentally can charge as a side effect of having a powered fan. Instead of a propane stove or the like, the idea is that this makes it easy to use small branches to cook breakfast or whatever.
The biggest criticism I've heard of this device is that it's a pain and highly inconvenient to constantly feed it twigs when you try to heat anything of consequence (e.g. pot of water).
You can argue that by growing the tree specifically to burn and then being careful how you harvest it, the wood burning ends up being carbon neutral. That's obviously not the case here, and it doesn't scale in general.
Add that this is relative to coal or oil or natural gas that have been carbon stored underground for millions of years.
This is not up for debate. It is not open for you to argue whether it "scales". It is the reality of the planet that we live on. Your opinion on it is utterly irrelevant.
And it's actually humorous that you mention forest fires given that removing the brush that camp stoves like this burns helps prevent forest fires, not to mention decomposition methane.
As to being rough on the lungs, the whole point of this whole initiative is clean burning the wood, eliminating the vast majority of particulate that is the result of an incomplete burn. I suspect you really don't care about the actual facts though, but just for anyone else coming along.
Absolutely not. For wood burning to be carbon neutral, you have to replace the wood and produce exactly zero CO2 during harvesting and transportation. Even if we gave your picking up twigs example a good 50yrs to cycle, you're removing fertilizer that would otherwise help the growth of current/new trees. There's a reason we put restrictions on wood burning and overall traffic in a lot of forest areas; it reduces the forestation.
> This is relative to coal or oil or natural gas that have been carbon stored underground for millions of years.
The length of the cycle doesn't make a difference because we're growing energy production exponentially and seeing consistent global deforestation (thus the scaling problem). That carbon from your stove might get replaced in 10-50 years.... if not for the environment suffering immediate effects that propagate.
> And it's actually humorous that you mention forest fires given that removing the brush that camp stoves like this burns helps prevent forest fires
Not in any significant way. As far as we know, forest fires are caused by weather patterns, forest life-cycles, insect life-cycles, ect. Clearing brush is a stop-gap fire fighters use to protect homes.
> As to being rough on the lungs, the whole point of this whole initiative is clean burning the wood, eliminating the vast majority of particulate that is the result of an incomplete burn.
The vast majority? I doubt either of us is going to do a study on this particular stove, but given that Biomass power facilities still produce large amounts of particulates, I'm pretty sure the little self-charging fan doesn't solve the problem.
> I suspect you really don't care about the actual facts though, but just for anyone else coming along.
I'm doing my best not to be confrontational, but your only "fact" is the misapplied notion that trees can only release carbon that they've previously absorbed. Every study I've read on using biomass for power generation has concluded that their only "environmental" advantage is that the fuel is easier to renew.
There is astonishingly little fertilizer potential of fallen wood (and the little there is remains in the ash). In parks it is controlled primarily because it acts as an ecosystem for levels of the pyramid, so overharvesting in dense areas is a problem.
"The vast majority? I doubt either of us is going to do a study on this particular stove"
Good thing we don't have to.
https://www.sbir.gov/sbirsearch/detail/390169
"carbon monoxide and particulate matter emissions reductions of 91% and 94%, respectively, while lowering fuel usage by 42%"
I'm doing my best not to be confrontational, but your only "fact" is the misapplied notion that trees can only release carbon that they've previously absorbed.
Well, it's good that you're not being confrontational, especially when you are speaking such utter nonsense, with a complete lack of any facts whatsoever. We are talking about a stove picking up scrap wood, which is, by every scientific definition on this great Earth, carbon neutral.
What possible reason could you have for thinking this? Pointing out that wood has been used in mulches and fertilizes for ... millenia ought to suffice, but since you seemed vexed by my lack of "facts". Here are some studies showing increased growth as a result of wood chip use -
http://www.cabdirect.org/abstracts/19910650274.html https://dl.sciencesocieties.org/publications/sssaj/abstracts...
Feel free to google as many more as you like.
> Good thing we don't have to.
From your link, "Standard water boil tests of early BioLite prototypes demonstrated carbon monoxide and particulate matter emissions reductions of 91% and 94%, respectively, while lowering fuel usage by 42% relative to a three stone fire"
So... not useful figures because they're from a prototype and not compared to another stove. I also wouldn't call that a vast majority in context since the relevant comparison is to a gas or alcohol fueled stove.
> Well, it's good that you're not being confrontational, especially when you are speaking such utter nonsense, with a complete lack of any facts whatsoever.
I was trying not to insult you by googling references for well-known results. That was evidently folly on my part -
http://www.midwestenergynews.com/2013/05/10/does-burning-woo... ( http://www.mass.gov/eea/docs/doer/renewables/biomass/manomet... , http://www.manomet.org/sites/default/files/publications_and_... ) http://www.pfpi.net/carbon-emissions http://www.saveamericasforests.org/Forests%20-%20Incinerator...
ect. ect. ect.
good summary - http://cleantechnica.com/2014/04/14/biomass-emissions-questi...
Further, the reduction was specifically about this method of burning wood versus your comical, hysterical claims. Wood burning creates soot and particulate when it is oxygen starved. The solution is to have a fan to feed it a steady supply. This is not rocket science.
Do you understand that we are talking about people burning twigs that have fallen to the ground? Do you understand how incredibly specious it is to talk about industry biomass production facilities.
I have never seen someone so profoundly wrong so steadfastly try to stick to an absolutely, utterly nonsensical opinion. You having NOTHING interesting to say on this. And filling your posts full of links saying nothing of the sort borders on pathological.
They're all about the complex carbon footprint of burning wood. Perhaps you might try explaining why they're unrelated.
> Wood burning creates soot and particulate when it is oxygen starved. The solution is to have a fan to feed it a steady supply.
Wood doesn't completely burn... when it doesn't completely burn. There are a lot of factors and a small fan doesn't solve all of them (this should be self-evident or the reduction would be 100%). Obviously, the comparison has to be made to stoves/generators using other fuels (ie gas/alcohol/petrol if you really want) because that was the original comparison - wood to other fuels, not wood burning stove to other inefficient wood burning method. Please refer back to the original post.
> Do you understand that we are talking about people burning twigs that have fallen to the ground? Do you understand how incredibly specious it is to talk about industry biomass production facilities.
If you'd bothered to read anything (the first article and associated reports go into a lot of depth on this), you'd see that burning dead branches sparingly (and correctly - this stove still has a lot of pollution relative to industrial methods) is one of the better methods. However, you have to be very careful about the type of wood you burn, the condition it's in when you burn it, the way you burn it, how much of it you remove, ect.
It's very complicated and in general it's done less efficiently than alternative fuels atm. The "ZOMG BURNING WOOD IS INHERENTLY CARBON NEUTRAL" thing is short-sighted and has been outdated for a good two decades now.
Do you want "facts" or not? Because you're not reading any of the ones I reference.
I think quite a few on this thread haven't camped or hiked enough to realize that cooking is an important part of those activities.
Burning hotter means better combustion and more efficient use of fuel. There are less particulates released.
Having said that, I tend to agree with you that this is green-wash and the stove is using a gimmick as a sales feature.
Seems pretty expensive for a wood burner.
It is an interesting novelty, but it is just so heavy, bulky, and slow that I am having trouble understanding who this would work for.
I'm a Scout leader and for a weekend camp will take a battery pack that will keep all our leader's phones charged for the weekend, but if it were any longer or wanted to give the neighbouring camps a charge, would need something solar or fuelled. From what I've seen of the solar stuff out there, most can't keep up with constant charging.
Unless you have scouts tending the BioLite constantly, I think it is definitely not a solution for groups.
The only scenario I can think of where the BioLite makes sense is if you have no access to electricity for weeks at a time. Even then I think solar panels make more sense.
(FWIW, I generally agree that it's probably not great for serious backpacking, but I had a lot of fun using while camping.)
I plan on winter hiking thru some areas with re-supply locations > 7 days apart and may use the biolite in place of my solar external battery (9.4 oz) since it will also serve for melting snow. I did not cook anything while on the AT (just soylent and mainstay bars) but I anticipate that warm meals will make winter hiking more enjoyable.
- Adjust the unit's placement so flames don't melt the power module - Make sure it doesn't overheat - Re-charge it when not in constant use
Also I can see myself burning my hands trying to wiggle USB plugs in.
Could've used more work in the product design department.
It works as described. However, you need to charge the power module before the first time you use it! The Biolite stove relies on fan assistance, so if there's no juice the stove won't work.
Once it's working, it works fine and charges the power module (via the built-in thermocouple).
The stove is designed to fold down and fit inside the optional kettle, so what superficially looks like a bulky kit is rather less so in practice. However, the stove+kettle combination weighs about 1.1Kg. There are lighter camp stoves out there (until you start adding in gas cylinders).
The optional grill doesn't seem to fold down/store concentrically with anything, so it adds bulk while costing rather more than rival cheap camping grils.
It seems kinda wrong to be out in nature, burning wood to charge a device. Why is this better than a small solar panel? A panel wouldn't have the fire danger, could be left out all day and charge its own batteries. Also, the efficiency of a TEC is really low, lower than solar panels by a pretty large margin.
You don't actually need to charge the power unit in order to use the stove; even if you start with a completely run-down battery, the unit will eventually generate enough electricity to start the fan and achieve maximum efficiency.
Also, it's always seemed to me that the Biolite is designed primarily as a reasonably efficient biomass stove—a role that, in my experience, it fulfills really well, even with wet wood. I've cooked plenty of meals on it, and it's much more convenient to carry around than a propane or white gas stove (as a bonus, you also don't walk around with explosives in your backpack).
The ability to charge devices is a happy byproduct. It's handy when you're cooking up some food and want to power up your phone or GPS receiver. It's probably not as efficient as a solar charges but (a) a solar charger won't cook food, so the Biolite is a convenient multitasker that requires less backpack room, and (b) the solar charger doesn't work at night, when it's cloudy, and so forth.
EDIT: FWIW, I also have a PowerPot, which is mentioned elsewhere in this thread. It's pretty cool, and works well; it's also my preferred charging method when I am not cooking, since I can just fill it with water and leave it on the campfire for as long as I need (the Biolite, on the other hand, needs constant feeding of fuel to continue running).
A phone might provide some safety while camping - but it absolutely would not be part of the safety planning.
You could also use battery power for torch-lights and music players.
Then there are things like GPS trackers, which can be useful after a trip to know where you had been.
The rated output (2-4W @ 5V) seems impressive, but I'm not certain I buy it or at least I'd wonder just how much you need to be feeding the fire. I don't see any mention of a battery pack, but I think if I'm charging expensive and sensitive devices I'd rather charge batteries, then charge my devices with a more stable current. Adding your own battery is going to bump the already-considerable weight (> 2lbs).
They do present a comparison to the "conventional alternative" of an alcohol stove + fuel + solar, but for some reason it seems designed to make the conventional alternative as unappealing as possible (44 oz & > $200 for a stove plus fuel for 2.5hrs of burn time!). Not included are options such as a simpler rocket stove (easy to make) or a SuperCat alcohol stove (cheap & REALLY easy to make) and options to make those more efficient (shrouds, etc. sized for your cookware).
As for charging, there are actually some pretty impressive solar options designed for backpacking - they aren't on-demand like this, but many of them incorporate a battery system and could likely be used on a pack while hiking, so the battery pack is available when you stop, and you can use them in places where you don't really want a fire.
I'd have to call this fashionable, but I'm not sure how practical it really is for most people.
Edit: forgot to mention, the base unit for this is ~$130, and the kettle/carrying case adds another $50 and 1 lb to the whole thing.
Grepping around the patent database doesn't turn up anything for the Powerpot, or assigned to Power Practical, or invented by Dave Toledo so I'm at a loss to know where they are on that.
That said, the tool, which requires boiling water only so that the correct temperature differential is maintained, seems a bit too specialized for back packing. It raises an interesting question on the weight budget for power though. I am guessing that a white gas fuel cell would be a much better answer from a practical point of view.
[1] https://www.youtube.com/watch?v=TZ5LAZJU2t0
[2] http://appft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=H...
However it seems that few people ever acknowledge that you basically have an at-will generator that you can carry in a pocket--albeit as long as it's a big pocket. So theoretically if you have this and a GPS unit, it's almost impossible to get lost, no matter how long you are out in the wild.
It may seem a bit bulky and there are lighter and more efficient ways to cook on the trail, but for the right sort of traveler, this stove is also bundled with some potentially life saving abilities.
My father once said a GPS is just a device to remind you how lost you are.
Our navigation "solution" was a laptop and Garmin GPS attached via USB. Laptop would be powered from car battery with power converter.
For software, we were going to use OziExplorer, which could display raster maps, and show current GPS location on them. Ozi maps are simply big raster images and there is limit of how big they can be.
Before the trip I found a tool that can scrape Google Maps satellite imagery and generate Ozi-compatible maps. So I ran it on the parts of Russia and Kazakhstan we expected to visit and got many gigabytes of cached satellite imagery.
During the trip as we moved along, I would use the tool to generate Ozi map for next area we were visiting. I got pretty handy at doing latitude and longitude bounding box calculations "in head" :-) To give idea of working conditions:
http://i.imgur.com/0k7AEE5.jpg http://i.imgur.com/X01vuNZ.jpg
There were various "oh shit" moments along the trip, one of which was when the power converter stopped working (and laptop's battery was empty because its charging circuit got fried earlier, guess because of the unstable power or overheating). GPS was still running on its internal battery so we did know our latitude and longitude and bearing. But our paper maps were not much use. The population density in steppe was so low, we could just drive until we'd run out of gas and water, and not meet anybody. I think we were shorter on water, as we had to use some of it to top up leaky radiators. Anyway, all ended well when our mechanic-guy found and fixed a simple wiring issue with the power converter, and we got the laptop back on!
So yes, you need GPS and maps.
(Which is your group's choice to make; I don't mean to moralize and lecturify, my earlier point was just to push back on the idea that a GPS and thermoelectric stove are safety equipment)
https://youtube.com/user/tetkoba
I'm more interested in these designs.
http://www.silverfire.us/scout-backpack-bug-out-stove
(No idea about that one in particular, just the first one I found when I went looking)
To put this in perspective compared to the new 1.2 V, 3500 mAh NiMH batteries (available for ~$1 each on eBay), let’s say we need 5 of them to go from 6 V to 5 V as they discharge. That’s a total of 17500 mAh (17.5 Ah). 5 V at 4 W is a current of 0.8 A by P = IV, so the batteries could run for just under 17.5/0.8 = 22 hours (slightly longer, since V > 5 which means I < 0.8).
They don’t say how much thermal wattage the stove puts out, but 1000 W electric camp stoves are readily available so I will go with that. 2-4 W of electric power translates to about 2-4% thermocouple efficiency which is pretty good.
I think perhaps in the near future we’ll see some innovations in heat engines like Stirlings which easily reach 50% of Carnot efficiency. They have a reputation for low power to size ratios, but that’s due to lack of compression (easily remedied if anyone, well, tried):
https://www.youtube.com/watch?v=H_Vnxapd5fs
The Carnot formula is:
Carnot efficiency = (T high - T low)/(T high)
So to boil water at 212 F (100 C or 373 K) at an ambient temperature of 72 F (22 C or 295 K):
Carnot efficiency = (373 - 295)/(373) ~= 21%
So a Stirling engine would achieve 10.5% at the heating surface, or about 2.6 times better than a thermocouple.
However, if we put the Stirling engine within the flame with modern ceramics and, say, graphite lubricant which can go to 842 F (450 C or 723 K), we could run at say 500 F (260 C or 533 K):
Carnot efficiency = (533 - 295)/(533) ~= 45%
So a Stirling engine would achieve 22.5% in the flame, or about 5.6 times better than a thermocouple.
Of course then you are dealing with moving parts and it would probably be unreliable. But the whole engine could be made airtight with the generator enclosed inside, so it might be possible to build one with a service interval of tens of thousands of hours or more.
Also I’m probably being too conservative on Stirling engine efficiency and too optimistic about thermocouple efficiency, so a Stirling engine is probably more like 5 to 10 times more efficient than a thermocouple.
I’ve often wondered if it’s possible to build a solid state device that raises the frequency of infrared radiation to the visible range so that it could be converted to electricity by a high efficiency photovoltaic cell. It can’t be done by concentration alone because the laws of thermodynamics state that concentrators can’t reach a temperature hotter than the source (5300 C for the surface of the sun), although using multiple cells optimized for specific frequency ranges seems promising:
https://en.wikipedia.org/wiki/Concentrated_solar_power#Effic...
I see that as perhaps one of the great engineering challenges of our time, because low temperature gradient free energy is all around us (orders of magnitude more than we could ever use) but we have no way to gather and concentrate it cheaply. So far this is the most promising method I’ve found for visible light:
https://en.wikipedia.org/wiki/Luminescent_solar_concentrator