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Ask HN: How innovative is the hydrogen industry?
33 points by danielovichdk on Nov 29, 2022 | hide | past | favorite | 48 comments
Sure it might seem as an odd question. But looking at renewable energy sector as a whole, how far is the hydrogen compared to others?

Any noticeable innovations? Any large difficulties?

I am curious since a client has approached me in this space and know very little of hydrogen innovation.

Thank you




It's a good question actually.

I think there is a lot of progress for hydrogen in small ways but to change the world there has to be a complete value chain from one end to another and that's been absent.

There are two scenarios for hydrogen: (1) as an energy carrier, (2) as an ingredient in industrial processes.

For (1) it faces stiff competition. For instance you could have a battery electric car instead of a hydrogen car. You could ship power via wires rather than a hydrogen pipeline, you can store energy for the grid in batteries or with hydroelectric storage instead of as hydrogen. Aviation fuel is a special hard case for decarbonization but aviation, particularly in terms of fuels, is one of the slowest innovation parts of the economy. Look at how long it has taken to get the lead out of GA fuels or for US airlines to upgrade their broken radar altimeters. Hydrogen has the advantage of high energy density by mass but very low volumetric energy density so everything from aircraft to infrastructure will be redesigned, I think the industry will be much happier to use synthetic fuels based on Fischer–Tropsch chemistry than change anything, although green hydrogen will be an ingredient of green synthetic fuels.

All of that makes me skeptical about (1).

There is a lot of talk about building electrolyzers and using green hydrogen for (2). The first phase of that is is replacing hydrogen made from fossil fuels.

Hydrogen is used to make ammonia, which is used to make nitrogen fertilizer. Hydrogen is used in oil refining and other chemistry. (Note that by current ESG rules, a company like Exxon Mobil doesn't get charged for the carbon in the fuels they sell, just for the carbon released by their oil refineries and other operations. With a 'green' oil refinery they could ship the same products they do now but still claim to be net zero for better or worse. By adding green hydrogen to a refinery they can ship more product per unit of crude oil and avoid waste CO₂)

There are other processes such as steelmaking, cement making, and glassmaking that require a high-temperature flame and where electric or nuclear heat would not be an option. For those a hydrogen flame fueled by green hydrogen could be an option. For metal production in general, hydrogen can substitute for the carbon monoxide that that is used to reduce iron in blast furnaces.


It seems like a nascent green hydrogen/ammonia industry is emerging - https://www.rechargenews.com/energy-transition/topsoe-wins-w...


You forget that (2) leads to a solution for (1). You also forget that every other way of moving or storing energy is facing competition from hydrogen. Something that they will struggle against because none of them have a decent (2).


I'm very skeptical of hydrogen as a general solution for reducing carbon emissions. It feels like greenwashing.

"As of 2020, the majority of hydrogen (∼95%) is produced from fossil fuels" https://en.wikipedia.org/wiki/Hydrogen_production

Producing "green hydrogen" is much more expensive: https://en.wikipedia.org/wiki/Green_hydrogen


WRT hydrogen engines: This video explains why using hydrogen to power an internal combustion engine doesn't make sense: https://www.youtube.com/watch?v=vJjKwSF9gT8

Lots of more informative responses in this thread than I can explain; just remember that a lot of people are promoting "hydrogen" in situations where it is either economically inferior to traditional batteries, or where the laws of physics make it impractical. (IE, the hydrogen V8 requires tanks so large that the vehicle is impractical.)

In whatever hydrogen space you're getting into, make sure you run the numbers like this video does. (IE, efficiency, volume of compressed hydrogen, energy lost to compressing / refrigerating, ect,) and make sure they make sense. For example, hydrogen might not make sense for day-to-day storage compared to a battery, but it may make perfect sense for a replacement for a standby generator.


Following up on my comment on a standby generator: There are a lot of places where the generator needs to be able to run for a few days, in poor weather. Think of the Texas blackout, with users like hospitals and data centers.

There's got to be a point where a fuel cell with a large tank of hydrogen is cheaper than a bigger battery. And, if you can hook in some kind of electrolysis thing, it could refill itself too.


As a great follow-up, Engineering Explained did a video on BMW's hydrogen car that used liquid Hydrogen.

https://www.youtube.com/watch?v=AouW9_jyZck

TL;DW - Liquid hydrogen is an even worse proposition, despite offering greater density than hydrogen gas.


First and foremost it is important to understand hydrogen is not a source of renewable energy. It is not like the sun or wind where there is an available, renewable, low carbon source of energy we can harvest. Hydrogen is only an energy storage mechanism. And it has efficiency vs weight vs volume tradeoffs compared with other storage mechanisms such as batteries or thermo-sand or hydro-gravity, etc.

Most of what is going on in the hydrogen space right now is that it is being leveraged by the fossil fuel industry to try to spread FUD around batteries and slow EV adoption. This is overshadowing the actual potential use cases for hydrogen, unfortunately.


The cynic in me wonders if hydrogen energy is:

1. Just a spoiler for renewables. Something that big oil and big gas can use to sew confusion and slow the transition to renewables.

2. A way that big oil and big gas can leverage their massive investment in fossil infratructure, even if it doesn't make sense economically or environmentally.

But I'm no expert on this. Just a cynic.


It's both of those things, but it's also a necessary and useful part of getting to net zero.

1 in particular was strong when Battery EVs were starting off. Don't bother with those early BEVs, just wait till the hydrogen fuel cell vehicles arrive. While fuel cell vehicles are actually cleanera nd greener than ICE, this went on much longer than was credible once it became obvious battery EVs were the winner in personal transport.

2. Oil and gas companies would really like to use blue hydrogen made from oil and gas and store the CO2 byproducts in oil fields. Or at least claim that they will store it. Luckily for everyone, the price crash in renewables means they'll be outcompeted if they try that and most governments have caught on e.g. the IRA stuff that varies support based on how clean the hydrogen production chain is.

But we need it to make fertilizer and other chemicals, and doing so with cheap renewables will save a lot of countries from being relient on fossil fuel providers.


But then why would Japan, a significant importer of fossil fuels, would be so heavily invested in Hydrogen ?


A political bet, with enough funding it might make it so… https://www.washingtonpost.com/climate-solutions/japan-hydro...


Japanese investment in hydrogen goes back to the 90s, before battery EVs (aside from the GM one) had proved practical. It was insurance against losing their auto industry if things moved away from gasoline ICEs. It has kind of had its own momentum since then.


Japan land isn't great for balanced natural energy buildings, so they want to continue import energy after carbon neutral, and hoard solar generated electricity. Nuclear is (was?) unpopular for obvious reason for a decade.


Here is the UK gov Hydrogen strategy that also has a recent update on the market: https://www.gov.uk/government/publications/uk-hydrogen-strat...

Hydrogen strategy update to the market: July 2022: https://assets.publishing.service.gov.uk/government/uploads/...

They (the UK gov) also have a portfolio of companies, they have invested in, that you can have a dig around for if u checkout current and previous Innovate UK funding rounds.

Probably worth checking out similar programmes from other tech focused government investments (US, Germany, etc.)


I think this was posted on HN a while back, can't find it, but the energy losses from production, to storage, through transport and delivery are much greater for hydrogen compared to electricity delivered on the grid and stored in lithium batteries. I think that, overall, there are very few applications where hydrogen makes sense. Even in places where the much greater energy density of hydrogen vs. lithium batteries matters a lot (e.g. aircraft), hydrogen is still not a great choice, and seems to me it would be better to just put research into making carbon-based fuels from renewable energy sources.


Hydrogen is a mature industry used in many ways with extensive long standing regulations which are plausibly overzealous because of the hindenburg and fear of hydrogen. Nobody will want to get their car's hydrogen tanks inspected several times a year.

95% of hydrogen is produced from fossil fuels. So if the intent is to get away from fossil fuels, which we must do regardless of political movements, then you haven't gotten away. It's a total failure path.

Furthermore, they have produced hydrogen explosion engines but such vehicles will be of low torque and low range. In most actual cases a hydrogen car is actually an electric car with minimal batteries and hydrogen range extension in a non-explosive fuel cell. Why not just put more batteries in your electric car and remove the hydrogen range extension?

If you want to do 'electrolysis' of converting water to hydrogen. It literally has a ceiling efficiency of around 60% depending on how industrial you wish to go. Your at home rig is going to be more like 15% efficient. Batteries are like 95% efficient. Why go hydrogen?

There have been claims of being able to use platinum or something to be more efficient but these have all died on the vine. Not unlike the dozens of new better batteries you will hear about.

In reality, even if they could produce hydrogen at >95% efficiency without fossil fuels. It's still the wrong solution.


> Why not just put more batteries in your electric car and remove the hydrogen range extension?

Presumably, because hydrogen is much quicker to refuel (than a battery charge) and hence can be done at a petrol stations same way we refuel petrol cars - i.e. without requiring the revolution of installing hundreds of millions of electric chargers across the world?


Number of locations is irrelevant when each location costs vastly less. Spending ~200+ billion on ~120,000 hydrogen stations plus even more to produce hydrogen in the US is vastly more expensive than millions of cheap charging locations.

So, in practice EV’s take less time to refuel than hydrogen. You plug it in somewhere you already want to be and then unplug vs going out of your way to drive to a hydrogen refueling station.

And that’s assuming we don’t electrify highways which would kill the last possible justification for hydrogen cars.


Its definitely a fair point. I'm sure fast charging will eventually become better and better as battery tech improves. Though also being able to deliver that much power to a bank of a dozen chargers will be a challenge I'm sure.

But it doesn't really explain why hydrogen can ever be a success.


It likes to recombine with oxygen at the slightest provocation.

Ignition energy in optimum concentration with O2 (or air) is 1.2J, the same as a ten cent piece falling on it's face from edge.

I've worked near a cold vent for hydrogen (eg disposed of to atmosphere, not deliberately flared) and you could hear when it used to ignite at the hint of any atmospheric electricity that was even over the horizon and not visible on a clear blue day.


That's an interesting question and it's also an important one because the answer will influence the future of our energy supply.

There are many good comments already so I will share an anecdote that might give an alternative view:

When I studied at the university we had a start-up come over to present their product. It was miniature fuel cells with the idea to use them to power mobile phones. It was the late nineties, mobile phones were all the rage and batteries were terribly bad. Students were pretty excited and the discussion after the presentation was a big hurray on hydrogen and fuel cells. A bright future ahead.

Until our professor wryly remarked: "Yeah, hydrogen is the technology which has been on the verge of a breakthrough for 30 years."

Whenever I hear about innovation in the hydrogen sector I must think of that quote, and that it's now another 30 years later, nothing has changed and we are still on verge of a breakthrough.

Does it mean that breakthrough will never come? Maybe. Maybe it will come, but I wouldn't be surprised if it takes another 30 years.


Hydrogen is a fake green fuel pushed my the petroleum industry. It is 100% not a viable fuel because it’s just oil with extra steps.

The recent astroturfing campaign is funded by petroleum companies.

1) the only reasonable way to make it is to crack it from petroleum 2) it’s hard to contain and ship so the infrastructure needs are substantial 3) nobody who knows about or cares about renewables takes it seriously.


Thanks, good to know.

"Thermal processes for hydrogen production typically involve steam reforming, a high-temperature process in which steam reacts with a hydrocarbon fuel to produce hydrogen. Many hydrocarbon fuels can be reformed to produce hydrogen, including natural gas, diesel, renewable liquid fuels, gasified coal, or gasified biomass. Today, about 95% of all hydrogen is produced from steam reforming of natural gas."

https://www.energy.gov/eere/fuelcells/hydrogen-fuel-basics


My understanding is that Hydrogen has energy-density problems as a fuel source. To have enough energy density to be useful for a vehicle, you need to keep it liquid. To keep it liquid, you need to refrigerate it - which takes energy.

So, I think the innovation in hydrogen is asymptotically limited by the physics of the H2 molecule.


The required (& wasted) energy - both for the initial liquefaction, and to keep it liquid - are only the beginnings of the pain of dealing with LH.

For starters: hydrogen boils at -250C, vs. oxygen at -180C. So a lowish-pressure tank of LH can naturally "condense" liquid oxygen (and nitrogen) from the atmosphere if there are flaws in the tank's insulation.

...and the rule of thumb is that one charcoal briquette soaked in liquid oxygen has roughly the explosive power of one stick of dynamite. (Unlike dynamite, the LOX-soaked briquette can detonate with neither apparent cause nor warning. And this effect is hardly unique to charcoal briquettes. Anything porous and combustible will do.)


Yup. BMW made a liquid hydrogen-powered car and the result is...not good. Nothing more than publicity stunt.

https://www.youtube.com/watch?v=AouW9_jyZck

The TL;DW is that since you can't keep it cold enough, eventually the liquid starts to convert to gas, pressure builds up in the tank, and a vent is needed to allow the hydrogen gas to escape.

Which then poses a problem, since hydrogen gas is VERY explosive, you can't keep this car in your garage. You have to keep it outside.

Then of course there's the issue of this comically large tank taking up the enter back of the car.


It’s a long road for hydrogen.

There isn’t that killer application yet that’ll definitely make hydrogen win out over fossil fuels or electric.

Electric cars have a big lead, and hydrogen cars would require a massive investment in hydrogen fueling stations. Similar story for trucking, though maybe hydrogen trucks would need a smaller web of fueling stations.

Home heat — again, need infra to pipe it to homes or even deliver by truck, there arent hydrogen compatible furnaces out there AFAIK.

Aviation is super interesting, as is cargo shipping.


Killer apps are steel production, fertilizer, and cargo ships that run on ammonia. Electricity is not a feasible replacement for any of those. Also hydrogen production can use excess solar power in the beginning and doesn't have an issue using intermittent energy sources like solar and wind.

There is definitely a large role for green hydrogen in the future, barring some crazy new technology being developed.


Yes a big investment is fueling stations would be needed, but as it stands the investment required for EV charging is huge as well. So may a key issue would be the difficulty to carry both out.

On the face of it hydrogen would be much less disruptive than EVs: you go to the station and you refuel in a similar way as now. For EVs there are many problems not resolved yet in order to support the day when all cars are electric.


It's the thing that comes after the wind and solar revolutions. Everyone dismissed wind and solar as they happened, usually via a combination of ignoring cost reductions or not grasping what exponential growth is. Hydrogen is following the same cost reduction and growth curves. It's basically history repeating for the third time. Everyone here who hasn't made this realization will be loudly proven wrong in the near future.


Just looking at energy storage/transmission, the experts I've heard that aren't clearly pushing hydrogen seem to think that it's going to be mostly a niche product.

Might be used for aircraft, ocean shipping, and other places where batteries don't have the requisite energy density and the refueling infrastructure can be installed in a limited number of places (ie, not for passenger vehicles).

Might be used for seasonal energy storage. Although there are relatively few places (salt caverns) in which to store it. Interestingly the same study concluded that natural gas + carbon capture is the next most economically feasible option. https://environment-review.yale.edu/power-127-hours-economic...

Might be stored in an easier-to-handle form - eg make hydrogen, turn it into ammonia, and store that. Of course that lowers the round-trip efficiency even more.

Some utilities have talked about injecting 5-10% hydrogen into the existing natural gas infrastructure to partially de-carbonize domestic heating.


I heard a CEO of a venture backed "green hydrogen" startup (valued at 1 Billion) say in a talk that they will only be profitable if society changes its habits and is willing to pay more for energy.

Not sure how true that is and with the current increase in energy prices in Europe, the break even point might be closer now than a year and a half ago.


Don Lancaster has been commenting on the absurdity of the hydrogen economy for over 20 years, saying hydrogen is a "pollution amplifier":

https://www.tinaja.com/h2gas01.shtml


There's a YC backed startup building a hydrogen hub and marketplace for the U.S.

https://www.phoenixhydrogen.com/


I'm sceptical of hydrogen for the basic reasons that it is low energy density and it is hard to store. It literally leaks through the walls of metal storage tanks. That said, there is work being done on alternative storage methods. If there is a significant breakthrough, there, it could mean hydrogen becomes useful as a store of energy in those few situations where alternatives just won't work.


Hydrogen is a very hard gas to use. If you talk to anyone who has shipped products using it (most likely in military/space applications), the fundamental behaviors of it in materials science are very difficult. It’ll make your nice fancy metal pipes flake apart. Good luck with any sort of gaskets. Being the smallest molecule means it will escape in a moment’s notice.


I don't know how practical this is, but I'd really like a hydrogen grill that I can plug into a wall and run a hose to.

I also wonder if the same concept would work for a hydrogen stovetop; perhaps even paired with a dehumidifier to keep my interior humidity under control.


I had the privilege of talking to a big investor in hydrogen fuel a few months ago so my answer will focus on hydrogen as a substitute for fossil fuels rather than the use of hydrogen elsewhere.

1/ Hydrogen cars and trucks exist but they break down a lot and they are not mass produced. There is no infrastructure to repair them either.

The investor is funding repair points and fuel points but the route has to be carefully planned to make sure the vehicle arrives to those points

2/ Hydrogen fuel distribution is almost non-existent at the moment (which was the main focus of this investor) and they were looking at building distribution points along the major road networks

It's a problem that electric cars don't face as electricity is already everywhere.

In the short term, only islands or otherwise very isolated road networks may convert to hydrogen fuel. And that's optimistic.


There are two big markets for hydrogen:

1. It is needed to make fertilizer and in other industrial processes. This need is constant, more or less, and is not going away. We need plants to eat.

2. It can be used as a fuel (for motors, heating, whatever). This need is currently low, but may grow. But so far, this area has been mostly a dud.

As far as innovation, the next big innovation is figuring out less polluting ways of creating hydrogen. Most hydrogen is currently created as a by-product of fossil fuel production. There's a need to figure out a cleaner way to make it that isn't so incredibly energy inefficient. Learn about the "colors" of hydrogen to see what options currently exist: https://www.nationalgrid.com/stories/energy-explained/hydrog...

The problem with hydrogen as a fuel is that it is much less efficient (from a pure physics perspective) than just storing electricity directly in a battery. If you generate 1 kilowatt hour of electricity, by the time you send it to a house, charge a car, and use it, about 75%-80% of the power makes it to your wheels. If you instead use hydrogen, only about 30% of the power makes it to your wheels. See: https://www.volkswagenag.com/content/dam/online-kommunikatio...

This creates the paradox that clean hydrogen produced from renewable energy is currently a net loss to meeting renewable energy goals. Any renewable energy you are putting toward creating clean hydrogen would be doubly efficient just used as electricity directly without the hydrogen step in the middle. In a world with infinite green energy, hydrogen would be great. But we aren't in that world.

The advantage that hydrogen has over batteries is that it can work in some circumstances where batteries are not yet practical - places where you need near-instant recharging or where where weight/total capacity is a big factor (i.e. maybe some airline applications, maybe ocean shipping, who knows).

So there are probably places where hydrogen will grow and be profitable. But it has pretty much completely failed in the automotive sector because batteries are just better and more efficient. Also note that a lot of the push for hydrogen over electricity is coming from the major hydrogen producers, which happen to be fossil fuel companies that want to stay in business and who happen to already sell hydrogen.


I'm not sure what you're asking, but the market is just about to take off. See this article I submitted recently:

A Breakneck Growth Pivot Nears for Green Hydrogen (bnef.com) https://news.ycombinator.com/item?id=33609423


I'm CEO at a YC-backed hydrogen startup (https://phoenixhydrogen.com/). Here's why I think hydrogen is cool:

1. If you believe in learning curves, you believe that green hydrogen will be cheaper than fossil fuels (per BTU or per kWh) in the foreseeable future. That doesn't mean we should use it for everything -- it will mostly be cheaper to use wind and solar power directly, or through batteries -- but it does mean we're likely to use a lot of it, especially given the following additional points.

2. Hydrogen is one of very few solutions to important classes of decarbonization problems. Basically, hydrogen lets us use electricity to replace fossil fuels in places where direct electrification is difficult. To summarize, this is mostly about contexts where we use fossil fuels as a feedstock (a physical ingredient), eg fertilizers or plastics or steel, or as a high-volume fuel for transportation (eg container ships or transcontinental flights) or energy storage.

3. Speaking of energy storage. Lots of people say hydrogen is a dumb way to store energy; we should use batteries instead. I agree we should deploy more KW of batteries than KW of fuel cells or hydrogen-fired turbines, but I also believe hydrogen is the cheapest solution to seasonal power storage. (NREL also believes this.) Did you know that America uses ~2x as much energy in February vs in October? When we replace gas and coal with wind and solar (or nuclear, whatever) are we going to build enough for February or enough for October? The answer is to build enough for the average load, and to use hydrogen to store the power in vast underground salt caverns. This is much cheaper than the obvious alternatives (overbuild wind+solar+batteries). Basically, a lowest-cost fossil-free system would have more KW of battery energy storage and more KWh of hydrogen energy storage.

4. Hydrogen is transmission, and especially in the US, that means it's a solution to the #1 bottleneck that is preventing the construction of new wind and solar plants. Wind and solar energy are cheap, but there is a literal corrupt monopoly system (power utilities) which prevent it from competing fairly with fossil fuels, or from being transported from resource-rich areas to demand centers. Lots of people don't know this, but "interconnection" (the rules which allow utilities to impose delays, fees, and clandestine sabotage upon new wind and solar projects) is the #1 problem facing renewable energy projects in the US. The "interconnection queue" is like a line that wind and solar projects must wait in for years before they learn if their request will be approved, denied, charged outrageous fees, or simply deferred. In some places (MISO) regulators have approved a "pause" in the interconnection queue, meaning that nobody is allowed to get in line for the next several years. Hydrogen can help clear this up, and isn't subject to the same monopolies in the same way; one hydrogen pipeline can move as much renewable energy as 5-10 giant transmission lines, using one 50' right-of-way and no visible infrastructure (vs transmission towers, 500'-2000' of right-of-way and 100'+ tall towers).

If you're a transmission nerd and you don't already love hydrogen, be aware that we are literally planning a US supergrid today, and it will be operational by 2030. It's just pipes instead of wires; it's arguably jankier (and arguably not https://www.sciencedirect.com/science/article/pii/S2211467X2...) but definitely capable of solving the problems that make us talk about supergrids.

5. Final reason hydrogen is cool: it is not innovative. Innovation in the energy sector is very hard! If nuclear SMRs follow the optimal path, it will be 2035 before they are deployed at GW scale, and 2060 before they are deployed at TW scale. That's because innovation is about things that haven't been done before, and that means risk, which is toxic poison for infrastructure finance. Hydrogen can ramp up that same scale way way faster (electrolyzers are ramping from 1MW to 1GW in annual US deployment between 2013-2023) because it's all dumb 1950s tech that has been extensively studied.

In summary: I'm on a team called "build wind and solar fast to replace fossil fuels", and I found hydrogen in the course of studying how our team wins. It's a really cool tool! Thanks for reading my rant.


Here in Western Australia we already have plans onboard to produce large amounts (ie a significant increase against existing global production) of green hydrogen (not blue) and to ship it as ammonia (H3N) to Europe and Asia as a fuel to generate off (solar | wind) peak electricity generation.

This seems to address most of the issues raised here in this HN thread - no hydrogen small engine issues, no hydrogen as a slippery small gas molecule issues, etc.


> .. one hydrogen pipeline can move as much renewable energy as 5-10 giant transmission lines, using one 50' right-of-way and no visible infrastructure (vs transmission towers, 500'-2000' of right-of-way and 100'+ tall towers).

This.

Most people don't seem to be aware of how massive the upgrades to a 100 % renewable electric grid would have to be. In order to always be able to transmit 100 % of available peak renewable energy from where it's produced to where it can be used.

Also, an electric grid is a much more fragile infrastructure than gas pipelines, which are in themselves a large buffer.


I think right now, almost noone can actually grasp how valuable the stability and anti-fragility of the current hydrocarbon-based energy system is to society (with ~ 85 % of all energy still being fossil).

The (necessary/inevitable) shift from that hydrocarbon system towards more and more electricity IMO will introduce more and more fragility.

Strategic oil reserves and natural gas reserves can supply nations for months of heating, car/truck driving and electricity generation.

Now shift all this to electric heating and EVs and the system will have a lot less buffer overall. It'll be weeks (and that's optimistic) instead of months.

Yes, sounds a bit like FUD even to myself, but this is what it looks like to me, when I try to look at the energy system in a more abstract way.


Developments such as passive heating homes that reduce energy consumption to almost zero, might solve these problems. But that'll take another 30 years at least.


I also like that you can produce green hydrogen anywhere there are natural resources not being used. (like climate depressed developing countries... ) Places where they get lots of sun can SHIP THEIR SUN to other places in the form of green hydrogen.

this is a great way to bring developing nations up in the economic world.

A little infrastructure and bingo these places now have a green export.


The answer is to build enough for the average load

Not really as the round trip efficiency of electricity to h2 to electricity again is only in the order of 30%. So it will be less attractive than that.




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