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Hi, It's always amazing to me how bad reporting about science and technology is.

 

The system is just one example of a Solid Oxide Fuel Cell. Siemens and other companies have been working on these things for a LONG time. http://en.wikipedia.org/wiki/Solid_oxide_fuel_cell

 

Basically, we're talking about "solid state" (i.e. no moving parts, no rotating turbines or reciprocating engines) electrical generators that use conventional fuels (natural gas, gasoline...) and have very good conversion efficiencies (reaching 60% in some cases). But these things operate on very high temperatures (around 1000ºC) and that creates a lot of (costly) headaches in terms of materials, durability and so on. The most promising (and energy-efficient) approach is with hybrid set-ups http://www.energy.siemens.com/hq/en/power-generation/fuel-cells/sofc-gt-hybrid.htm

 

I'm really hopeful about this kind of tech in the medium term, but this is a heavily populated field, and the buzz about the "Bloom Box" makes it sound as if it's just a breakthrough achievement by this fancy start-up. Check for example:

 

http://fossil.energy.gov/programs/powersystems/fuelcells/fuelcells_solidoxide.html

http://www.fuelcellmarkets.com/fuel_cell_markets/solid_oxide_fuel_cells_sofc/4,1,1,2503.html

http://www.fuelcellmarkets.com/fuel_cell_markets/industry/2,1,1,7.html?q=solid_oxide_fuel_cells_sofc

 

They possibly have a better future than the more widely known PEM (Proton Exchange Membrane) Fuel Cells. But I'm not sure this is clearly actionable investing knowledge. And regarding PEM fuel cells, ask investors in BLDP how they feel about the promise of fuel cells :-)

 

Best regards,

Bastida.

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The main technology drive behind the commercialization of fuel cells is the maintenance of the existing corporate business infrastructure that sells you stuff through a pump. (Hydrogen instead of gas).  Chemically and physically they are a disaster so they will never become viable.  There is no point using electricity to make hydrogen, (which is adding an electron to an atom 2000 times it's size) transporting it to a filling station to pump into your tank to run through a device (the fuel cell) to strip off the electron for use in an electric motor when you can just obtain the electron directly through an existing electric grid.

 

They only work for the company pumping fuel - the rest of us are patsies!

 

Put your skills to work elsewhere - fuel cells are a mugs game  (bld)

 

 

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The main technology drive behind the commercialization of fuel cells is the maintenance of the existing corporate business infrastructure that sells you stuff through a pump. (Hydrogen instead of gas).  Chemically and physically they are a disaster so they will never become viable.  There is no point using electricity to make hydrogen, (which is adding an electron to an atom 2000 times it's size) transporting it to a filling station to pump into your tank to run through a device (the fuel cell) to strip off the electron for use in an electric motor when you can just obtain the electron directly through an existing electric grid.

 

They only work for the company pumping fuel - the rest of us are patsies!

 

Put your skills to work elsewhere - fuel cells are a mugs game  (bld)

 

 

Keep in mind that these gizmos work directly with plain natural gas, not with hydrogen (as is usually the case with PEM). THAT is really a non-starter. A pipeline wouldn't last more than a few years transporting H2 before you have to replace the whole thing: the tiny hydrogen molecules have the nasty tendency to diffuse into metals making them brittle, and it's not something easy to avoid.

 

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I didn't realize they ran directly off the gas.  As long as they don't actually burn the natural gas then there's probably something interesting there.  If they burn the gas then might as well just generate electricity with it as there would be no environmental benefit.

 

Indeed. The only environmental benefit of this device is in the form of (significantly) increased efficiency and absence of some combustion gases other than CO2.

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I watched a repeat of a nova documentary last week "Extreme Ice"

http://www.pbs.org/wgbh/nova/extremeice/

 

It freaked me out. I mean some scientists think it's possible that greenland's ice may no longer exist is frightening.

 

Were I live in Canada, replacement furnaces with less than 92% efficiency are banned.

 

I'm really wondering what kind of world my infants son's children will be born into.

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I don't see how this thing is going to use solar as a fuel source.  That's bad science reporting.  I think they meant to say the box could use hydrogen from a solar conversion system.  Depending on the solar conversion system, this might push the efficiency of the system even lower.

 

What you guys are missing here is that this system allows for a localized energy source that runs 24 x 7.  Most renewable energy sources are cyclical and inconsistent in power output.  What this system could use is a new solar conversion system that generates hydrogen from water.  There is some groundbreaking research in that field.  One of the products of this research is an electrode that converts water to hydrogen in direct sunlight.  The hydrogen could be captured and stored locally to power the system at night.  

 

I'm pretty skeptical, though, of any renewable energy technologies.  Some low tech ideas have very good to infinite ROI's, but these electricity producing green technologies suffer in this dept.  I'd like to know what the ROI of this system is, and what the efficiency conversion percentage is for natural gas and hydrogen.  That would be key.  If it converts at hydro power efficiencies, awesome.

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I'm pretty skeptical, though, of any renewable energy technologies.  Some low tech ideas have very good to infinite ROI's, but these electricity producing green technologies suffer in this dept.  I'd like to know what the ROI of this system is, and what the efficiency conversion percentage is for natural gas and hydrogen.  That would be key.  If it converts at hydro power efficiencies, awesome.

 

I saw one quickie estimate in passing the other day.  IIRC, 100+ year payback time on current models. 

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What you guys are missing here is that this system allows for a localized energy source that runs 24 x 7.  Most renewable energy sources are cyclical and inconsistent in power output.  

 

Actually, this allows for local generation as ANY conventional generator (gas turbines, conventional diesel generators) and it's as renewable as those (i.e. not at all). It's just more efficient and convenient (less noise, vibration, smokes...).

 

This is not a renewable energy source, except where you use landfill gas an that kind of thing, but then any gas burning generator would also be renewable. This thing is just a better fuel-based generator.

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it sounds to me like a great technology except . . . did they say you need to put oxygen in one side and fuel in the other?

 

If the "oxygen" side can use regular air this sounds great. If it needs pure oxygen then whats the point?

 

It runs with plain old filtered air (the guy in the documentary explains that dirty filters are one of the usual causes of downtime).

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I made a mistake in my earlier post.  I meant to say that the solar conversion electrode converts water into hydrogen.  And yes, this technology utilizes plain air.  It's basically the same fuel cell technology that is making its way into cars.

 

Bastida, it is renewable.  You can convert water into hydrogen via electrolysis in minutes, and that hydrogen can be a portable fuel supply.  When it was mentioned that this system can run on landfill gas, I believe they were referring to methane.  This could also be bad science reporting here.  Methane is the largest component of lfg, as you probably already know.  Also, methane, or natural gas, is much more renewable than say oil or coal--which is definitely not a renewable fuel since it takes millions of years via natural processes to produce.  Methane can be easily produced as a byproduct of cellular metabolism.  Bacterias produce it daily.  Cows fart it all the time.  Some humans produce it too.  Oil and coal, on the other hand...  So, I would say this technology is a renewable energy technology and definitely not like a diesel generator.  Any other conventional generator that uses methane should also be considered somewhat renewable.  Methane can be produced at will.  In fact, there are methane producing bacterias that degrades plastics.  The goal is to create a strain of bacteria that's able to do this even more quickly.  

 

The other key challenge for renewable energy is finding a technology that is able to fulfill the world's energy demands.  Currently, none even come close.  It only takes 4 regular nuclear reactors to produce as much kilowatts in a year as all the wind turbines in the U.S.A.  That is not good.  Hydro power, although very good and efficient, can only supply 5% of the world's energy demands at peak realization.  Fossil fuels are not going away in the next 50 years, if ever.

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Bastida, it is renewable.  You can convert water into hydrogen via electrolysis in minutes, and that hydrogen can be a portable fuel supply.  When it was mentioned that this system can run on landfill gas, I believe they were referring to methane.  This could also be bad science reporting here.  Methane is the largest component of lfg, as you probably already know.  Also, methane, or natural gas, is much more renewable than say oil or coal--which is definitely not a renewable fuel since it takes millions of years via natural processes to produce.  Methane can be easily produced as a byproduct of cellular metabolism.  Bacterias produce it daily.  Cows fart it all the time.  Some humans produce it too.  Oil and coal, on the other hand...  So, I would say this technology is a renewable energy technology and definitely not like a diesel generator.  Any other conventional generator that uses methane should also be considered somewhat renewable.  Methane can be produced at will.  In fact, there are methane producing bacterias that degrades plastics.  The goal is to create a strain of bacteria that's able to do this even more quickly.  

 

The other key challenge for renewable energy is finding a technology that is able to fulfill the world's energy demands.  Currently, none even come close.  It only takes 4 regular nuclear reactors to produce as much kilowatts in a year as all the wind turbines in the U.S.A.  That is not good.  Hydro power, although very good and efficient, can only supply 5% of the world's energy demands at peak realization.  Fossil fuels are not going away in the next 50 years, if ever.

 

Hi kawikaho, the Bloom Box runs on natural gas (methane, basically) not hydrogen. PEM fuel cells usually run on hydrogen (if you feed them with conventional fuels you need a "reformer" to obtain the H2 from them, although there are some Direct Methanol PEM FCs).

 

Actually, it's way more efficient to get the H2 from nat-gas than from water. But yes, if you want to make a fuel cell system renewable you need to get your hydrogen (if that's what your fuel cell runs on) from renewable sources of energy (and from water and not fossil fuels). But that's not how the Bloom Box works. And there's a reason for that: inefficiencies compound.

 

Let's see a simple example of the solar-hydrogen stack.

 

Sun Light -> Solar panel -> Hydrolizer -> Hydrogen -> Fuel Cell -> Electricity

 

Photovoltaic conversion is not very efficient, let's say 18% (a very expensive panel) and that's better than most installed systems. Hydrolysis is an atrociously inefficient process, and incredibly difficult to catalyze. Industrial-scale hydrolyzers run at efficiencies of around 40-43%. Let's assume that you can keep your Hydrogen storage without significant energy penalties (a big assumption, actually); you then feed your fuel cell that runs at a nice 60% efficiency. Well, this system has a total conversion efficiency of 4.32%.

 

We can now use solar-equivalent hours from this handy table (http://www.solar4power.com/solar-power-insolation-window.html) and pick, let's say, LA: 5.62 kWh per day per sq meter (yearly average). The average daily electrical consumption of an American house (2005 data, sorry) is 31.3 kWh. Our fancy solar to hydrogen to electricity system produces 0,24 kWh per day per square meter.

 

We just need 129 sq meters (1388 sq ft) of panels to run the whole thing. In addition to an industry-like efficient hydrolyzer, a yet-to-be-invented hydrogen storage system and a reliable fuel cell. I don't see how such an installation would ever break even.

 

The big, big problem with the so-called "hydrogen economy" is that hydrogen is a NIGHTMARE to produce, store and transport. It burns nicely and cleanly, though :-)

 

If we take the approach of using "sustainable" methane (landfill gas and so on...), yes, the system would be totally renewable and free of all the problems that hydrogen entails. But as you mention, in that case advanced conventional nat-gas generators would be just as good. Even for local distributed generation with cool stuff like what Capstone (CPST) sells.

 

Best regards,

Bastida

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I made a mistake in my earlier post.  I meant to say that the solar conversion electrode converts water into hydrogen.  And yes, this technology utilizes plain air.  It's basically the same fuel cell technology that is making its way into cars.

 

Bastida, it is renewable.  You can convert water into hydrogen via electrolysis in minutes, and that hydrogen can be a portable fuel supply.  When it was mentioned that this system can run on landfill gas, I believe they were referring to methane.  This could also be bad science reporting here.  Methane is the largest component of lfg, as you probably already know.  Also, methane, or natural gas, is much more renewable than say oil or coal--which is definitely not a renewable fuel since it takes millions of years via natural processes to produce.  Methane can be easily produced as a byproduct of cellular metabolism.  Bacterias produce it daily.  Cows fart it all the time.  Some humans produce it too.  Oil and coal, on the other hand...  So, I would say this technology is a renewable energy technology and definitely not like a diesel generator.  Any other conventional generator that uses methane should also be considered somewhat renewable.  Methane can be produced at will.  In fact, there are methane producing bacterias that degrades plastics.  The goal is to create a strain of bacteria that's able to do this even more quickly.  

 

The other key challenge for renewable energy is finding a technology that is able to fulfill the world's energy demands.  Currently, none even come close.  It only takes 4 regular nuclear reactors to produce as much kilowatts in a year as all the wind turbines in the U.S.A.  That is not good.  Hydro power, although very good and efficient, can only supply 5% of the world's energy demands at peak realization.  Fossil fuels are not going away in the next 50 years, if ever.

 

 

Let's see.  We stable a cow in our back yard.  Then we attach a funnel with a hose to her rear end.  Then, we vent the bovine's gaseous emissions to a holding tank connected to a high tech fuel cell that also receives explosive hydrogen bubbling up from electrodes in our swimming pool that are connected to solar cells on our roof.  Oh, I left out the most important part of all.  We scoop the poop produced by the cow (augmented by "honey pots" we carry down from our toilets after saving water by not flushing) and dump this into an anaerobic bacteria digestor tank that will generate ten times as much gas as we get directly from the cow.  . . . Then we . . . Then we. ? ? ?

 

Rube Goldberg, where are you?  We need you now!

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Years ago I worked in a hydrogen fuel cell development lab.  I actually installed parts on the first hydrogen FC powered vehicle ever licensed to drive the the roads of California, powered by a fuel cell developed and manufactured right there in that lab.  It was basically a modified golf cart and it cost well over a million dollars.  That experience notwithstanding, I can't add a whole lot to comments already made to this thread, but I'll throw my two cents in anyway.

 

First, I agree that this 60 Minutes was spectacularly bad reporting.  Given the target audience I understand they had to dumb it down some but fuel cells have been around a while and there were some pretty critical elements of the story they glossed over, doing a disservice to their viewers in the process.

 

I also agree with the poster above ( I think it was Bastida) who pointed out there's not a lot of difference between this and any combustion based fossil fuel generator, it's just a bit more efficient.  I'd point out though that the biggest efficiency gain has less to do with the delta between this unit's specific conversion efficiency and that of a comparable IC engine or turbine, and more to do with eliminating the 30% loss you eliminate by putting the generation closer to the point of consumption.

 

I'd furthermore point out that where renewable fuels like landfill or digester are concerned (I know a bit about those too and am currently working on development projects in both areas), the methane content of those gases tends to be only about 50% of what you get in geologic natural gas.  Most of the rest is CO2, water vapor, and relatively benign constituents, but there are also significant organic and inorganic contaminants that can be highly corrosive to equipment as well as produce toxic emissions and are subject to air quality control constraints.  These introduce non-trivial costs to the entire system and greatly impact maintenance and life cycle timing.

 

I'd still like to believe there is a future for fuel cells, but frankly where combustible fuels are used I don't see the point.  There are 30kW microturbines that fit in a wheelbarrow and have a single moving part that spins on air bearings requiring no lubrication that, when installed where waste heat can be put to good use can compete with fuel cell efficiencies at a fraction of the cost.  But I believe despite the system inefficiencies described above in the total solar-hydrogen-fuel cell cycle, it's a system that has a lot of long term potential.  It drives me nuts when people start off talking about solar conversion efficiencies as though it's no different than combustion efficiency.  Solar energy is free.  It doesn't matter if your conversion efficiency is just 1%.  The primary reference point is installed cost per watt, and even that doesn't matter as much as life cycle cost per kilowatt hour (this is a subtle point but it makes a big difference when comparing different PV technologies).

 

Over the long haul, PV costs will continue to come down, perhaps not quite in line with Moore's Law but I really do believe we're no more than a human generation away from building integrated PV where we wouldn't consider putting a roof on a new building that doesn't generate electricity.  It will be a long time before we get to where the grid can't absorb whatever is not used locally, but eventually storage will be a requirement, and it already is a requirement where the grid is not part of the equation.  Conventional batteries can fill that role but they are expensive and they do wear out.  Hydrogen storage is the answer to that problem, but not without its own challenges are articulated by others here. 

 

Not often talked about because it's not well understood is that we already have a pretty darn good hydrogen storage and transport technology that many of us use daily.  Nickel metal hydride (NiMH) batteries are extremely common and I'll bet every person reading this owns at least a few of them, be they rechargeable drills or flashlights or whatever.  They're not quite as energy dense as lithium ion and don't get as much buzz, but they're cheaper, they last longer, and they're not subject to the lithium material constraint that I guarantee is going to prevent Li from being the global EV solution.  All Toyota Prius and most other HEVs on the road have been using NiMH for over a decade. 

 

All a NiMH battery is is a hydrogen fuel cell with onboard H2 storage.  Add plumbing to supply an external source of air and H2 and you've got the whole package.  The metal hydride stores hydrogen gas in a solid form at extreme densities compared to compressing the gas and the plumbing is simple enough that you can get away with using stainless steel so hydrogen embrittlement isn't that big an issue. 

 

Honestly, the biggest problem with the whole system is that the genius who invented it all over 40 years ago was a pure scientist with no business sense whatsoever and in an effort to keep his labs open and developing new gee-whiz technologies that really do work and really are cost effective, he allowed other larger corporations to take control of all the potential profits which in turn have kept a lid on what he's been able to get to market.  Hence Energy Conversion Devices (ENER) is right up there with Ballard (BLDP) in the pantheon of failed alternative energy investments.  But Stan Ovshinsky was pushed aside a couple years ago and there are much more business oriented people running things now.  I'm still hopeful for the future of this technology.

 

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I don't know that it was bad reporting. He purposely only gave a glimpse and few details to the Bloom device, a clever marketing ploy. They even have a countdown clock on their website that upon completion will unveil more press info, it could be an interesting event (about 2 hours from now).

 

In a rarely seen flood of interest in a previously little-known company, Bloom Energy Corp. is set to officially unveil what it calls a break-through in fuel cell technology on Wednesday.

 

The Sunnyvale company lifted the veil slightly in a "60 Minutes" episode on Sunday that triggered a wave of inquiries about what it does.

 

Among those expected to be on hand Wednesday are Gov. Arnold Schwarzenegger and Colin Powell, the former secretary of state, and prominent venture investor John Doerr. Both Powell and Doerr are members of Bloom’s board.

 

Bloom CEO K. R. Sridhar claimed in the TV story that devices made by his company generate electricity at a cost of 8 to 10 cents a kilowatt hour using natural gas, lower than commercial prices in some parts of the country.

 

The fuel cell boxes are roughly the size of a parking space, cost $700,000 to $800,000 and have been tested by Google Inc., Wal-Mart Stores Inc., Bank of America and other large corporations.

 

Bloom is hardly an overnight success story, however, raising $400 million and taking eight years to develop a new type of solid oxide fuel cell.

 

Despite the claims and the publicity, questions remain on the company’s technology that may begin to be answered with Wednesday's press conference. Fuel cell adoption to date has been limited by their cost and durability.

 

Among the financial backers of Bloom are Menlo Park venture firms Kleiner Perkins Caufield & Byers and New Enterprise Associates.

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I also agree with the poster above ( I think it was Bastida) who pointed out there's not a lot of difference between this and any combustion based fossil fuel generator, it's just a bit more efficient.  I'd point out though that the biggest efficiency gain has less to do with the delta between this unit's specific conversion efficiency and that of a comparable IC engine or turbine, and more to do with eliminating the 30% loss you eliminate by putting the generation closer to the point of consumption.

 

Well, line-loss is clearly an additional concern. Transporting nat-gas is a little bit more efficient than electricity but I don't see a difference as big as 30%. Here in Spain, average electricity line-loss is around 20%.

 

It drives me nuts when people start off talking about solar conversion efficiencies as though it's no different than combustion efficiency.  Solar energy is free.  It doesn't matter if your conversion efficiency is just 1%.  The primary reference point is installed cost per watt, and even that doesn't matter as much as life cycle cost per kilowatt hour (this is a subtle point but it makes a big difference when comparing different PV technologies).

 

Isn't conversion efficiency a BIG factor in determining cost per watt? Because you need to take into account effective installed watts. I'm tired of hearing about "4kW (peak)" solar panels, giving the impression that the thing is able to output that for more than about 40 minutes a day. In determining the cost of an installation that provides X kWh per day to cover specific needs, of course conversion efficiency matters. Having horrible conversion rates is not good, regardless of the primary energy source (but yes, it's a bigger problem when you start from fossil fuels).

 

Best regards,

Bastida.

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Watching a live blogging of the event, as i couldn't find a live video stream. Latest Tweet:

 

9:31AM Coming on stage: John Donaho of eBay, Bill Simon of Walmart, ... FedEx, Cox, Brian Kelly of Coca-Cola, and Google's Larry Page. There are quite a number of heavy hitters on stage.

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"Walmart has completed installation at two stores in southern California, each at 400kW, generating approximately 3.4 million kWh annually. Each of these sites has the potential to eliminate 1 million pounds of CO2 annually when powered by biogas."

 

So with a 3 to 5 year pay back stated on the bloomenergy.com website and power in California I think is about $0.10 per Kwh the cost of each 400 kWh installation producing 3.4M kWh per year is about $340,000 x 4 = $1.36M. The inputs are heat (self-generated), air and natural gas or biogas and the outputs include pure DC power, pure carbon dioxide and presumably some heat and you can reverse the process to make hydrogen. Water is reformed and recirculated.

 

If true this is huge. Why wouldn't Google install it in every data centre and Walmart install it at every store? The rate of return is about 20% per year to give a 3 to 5 year payback. Some companies could use the other outputs which will boost the return. This is good news for US companies that can buy the limited supply, good for natural gas producers, good for hydrogen or electric vehicle makers and bad for power utilities, nuclear and coal related companies and power line producers. It will also be bad for solar because why put up the capital cost for solar if less money gives you clean power 24/7. It is way cheaper to put a small box outside than it is to put a vast solar array on a roof.

 

By distributing natural gas instead of power we save the 30% power line losses. If a direct or indirect carbon tax is introduced the economics get even better. Now I can see why Kleiner invested $400M.

 

 

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If true this is huge. Why wouldn't Google install it in every data centre and Walmart install it at every store? The rate of return is about 20% per year to give a 3 to 5 year payback.

 

I think they mean that you will save an amount equal to what you paid over 3-5 years . . . kind of like paying par for a 4 year zero-coupon bond.

 

Even so I think this is very exciting, I wonder how long these last though. I think I have seen figures for these types of cells that suggest 5% annual degredation (not sure if this is in efficiency, capacity or both).  I would much rather have natural gas delivered to my home/business and run one of these, even if the economics are only mildly robust over ten years than deal with the incompetent and inneficient power generation/transmission system (in suburban US with ~10 power outtages per year)

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No... I believe I read that the Bloom Box is a flex fuel system.  It can use hydrogen, natural gas, and even solar??  So, I think you're wrong here.  And, no, it's definitely not much more efficient to get hydrogen from methane than water.  The difference in bond dissociation energies to remove 2 hydrogen atoms is only about 20 kJ/mol.  Besides, water is everywhere, and it's highly renewable.  Methane, although being much more renewable than say OIL, still needs some work to renew or produce.  It's also not everywhere.

 

I believe you didn't read what I was saying.  I've already said depending on the solar conversion system, the efficiency of coupling that with a Bloom Box would drive the efficiency of the system lower.  No shit solar PV is inefficient.  I've already said the ROIs on most of these electricity producing technologies are bad.  If you read my post, you would see I was not talking about solar PV.  I was talking about newer electrodes that uses sunlight directly to do the hydrolysis.  The use of solar PV would undermine any system.

 

twocowcfa, the point is methane is easily renewable.  Do you see anything farting out oil?  Geezus.  And hydrogen isn't naturally explosive.  It's flammable, but not explosive.  I would say gasoline is way more explosive than hydrogen.  The old vintage footage of the Hindenburg disaster showed the blimp slowly burning, not exploding.  

 

 

Hi kawikaho, the Bloom Box runs on natural gas (methane, basically) not hydrogen. PEM fuel cells usually run on hydrogen (if you feed them with conventional fuels you need a "reformer" to obtain the H2 from them, although there are some Direct Methanol PEM FCs).

 

Actually, it's way more efficient to get the H2 from nat-gas than from water. But yes, if you want to make a fuel cell system renewable you need to get your hydrogen (if that's what your fuel cell runs on) from renewable sources of energy (and from water and not fossil fuels). But that's not how the Bloom Box works. And there's a reason for that: inefficiencies compound.

 

Let's see a simple example of the solar-hydrogen stack.

 

Sun Light -> Solar panel -> Hydrolizer -> Hydrogen -> Fuel Cell -> Electricity

 

Photovoltaic conversion is not very efficient, let's say 18% (a very expensive panel) and that's better than most installed systems. Hydrolysis is an atrociously inefficient process, and incredibly difficult to catalyze. Industrial-scale hydrolyzers run at efficiencies of around 40-43%. Let's assume that you can keep your Hydrogen storage without significant energy penalties (a big assumption, actually); you then feed your fuel cell that runs at a nice 60% efficiency. Well, this system has a total conversion efficiency of 4.32%.

 

We can now use solar-equivalent hours from this handy table (http://www.solar4power.com/solar-power-insolation-window.html) and pick, let's say, LA: 5.62 kWh per day per sq meter (yearly average). The average daily electrical consumption of an American house (2005 data, sorry) is 31.3 kWh. Our fancy solar to hydrogen to electricity system produces 0,24 kWh per day per square meter.

 

We just need 129 sq meters (1388 sq ft) of panels to run the whole thing. In addition to an industry-like efficient hydrolyzer, a yet-to-be-invented hydrogen storage system and a reliable fuel cell. I don't see how such an installation would ever break even.

 

The big, big problem with the so-called "hydrogen economy" is that hydrogen is a NIGHTMARE to produce, store and transport. It burns nicely and cleanly, though :-)

 

If we take the approach of using "sustainable" methane (landfill gas and so on...), yes, the system would be totally renewable and free of all the problems that hydrogen entails. But as you mention, in that case advanced conventional nat-gas generators would be just as good. Even for local distributed generation with cool stuff like what Capstone (CPST) sells.

 

Best regards,

Bastida

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Isn't conversion efficiency a BIG factor in determining cost per watt? Because you need to take into account effective installed watts. I'm tired of hearing about "4kW (peak)" solar panels, giving the impression that the thing is able to output that for more than about 40 minutes a day. In determining the cost of an installation that provides X kWh per day to cover specific needs, of course conversion efficiency matters. Having horrible conversion rates is not good, regardless of the primary energy source (but yes, it's a bigger problem when you start from fossil fuels).

 

Best regards,

Bastida.

 

I think we're basically making the same point, which is that if you can produce 8% efficient PV for less per kWh produced than higher quality 18% PV, what difference does it make?  It's not like you're wasting the primary energy input because there's always more sun.

 

Toward that end, Unisolar thin film PV, which is markedly less efficient than most other PV products in terms of watts per square meter, and also a bit more expensive on a dollars per installed PEAK watt basis, actually produces more kWh at a lower cost because it's capable of making use of lower light conditions.  Where more efficient panels don't start pumping electrons at all until they're under full sun, Unisolar's laminates begin producing energy at first light and keep right on producing up until dusk.  That doesn't make them better for all applications, but it certainly makes them the best choice for many...particularly when you consider that Building Integrated Photovoltaics (BIPV) are actually part of the building envelope.  They are the actual roof membrane, so they offset other costs.  There are no roof penetrations, no structural loading requirements, they can handle higher winds so they won't fly off in hurricane country, and you can even walk on them or put a bullet through them and they'll keep right on working.  

 

It's no small coincidence that it's the same basis in physics that governs how this amorphous silocon PV works that makes the NiMH battery work.

 

I should add in the interest of full disclosure that I am talking my book here.  I've been long ENER for a long time and am deep in the hole on it.  So as far as investment advice I'm the last guy you should listen to.  But as an energy engineer I know what I'm talking about and whatever happens to the company that owns this technology today, the technology itself is going to be around for a long, long time.  If that's not bad enough, I'm also long Capstone Microturbine.

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