Thank you for this! The Naturschutzbund (German nature conservation society) is a credible source. Birds of prey (and vultures) are the top predators and don't have to look out for others, they look for mice. A massive expansion of land based wind turbines will have its effects on birds (and even will slow the wind down, helped by reforestation).
Thanks for this! Still want to do some math myself.
But do you happen to know if they actually did something new?
The are some thoughts about storing wind energy as H2 to secure energy supply. OK. If you want an uninterrupted supply of 1 wind turbine then, assuming for ease of the calculation that a wind turbine normally only produces 33% of the time (it is a little bit higher than 33% but definitively less than 50%), then you will need 3 turbines if you discard any conversion losses. This extra production has to be stored and batteries are not a real option.
Now factor in conversion losses. Electricity from the turbine -> some synthetic fuel (H2?) -> burn -> electricity. If each step is 90% efficient (quite good) then we have 73%. With 80% (still good) it is 52%. However H2 has its issues so let us convert it to an easy simple fuel (for storage and transport) like gasoline, diesel, or kerosine which you can store as a liquid (e.g. in a simple jerrycan). So an additional step. With 90% you will find 65% overall, and 80% gives 40%. With 90% efficiency the 2 extra turbines require 1 extra turbine, with 80% you will need 3 extra wind turbines. So to secure long term energy of 1 wind turbine you will need 4 to 6 wind turbines. If you don't want the extra turbines (or nowhere to put them), then what do you use? Gas turbines ... (you can switch them on and off when needed, somehow I am not so keen on nuclear).
Sorry but I get horror visions of the north sea (with devastating effects because of the noise for sea life (whales, dolphins), and migrating birds) or landscapes (birds of prey look downward, there was this rare bearded vulture who wandered into the Netherlands who was chopped in half in May).
Agreed that you would need to factor in a high level of redundancy if you want to power the whole thing with wind or PV. Not entirely sure about the environmental impact of wind farms. Totally agree that they are an eyesore. And I know you need to protect offshore farms from scouring, which basically creates a reef around each one. But this might actually be beneficial to local marine biodiversity. Birds it seems, learn the hard way, but learn quite fast.
Agreed that burning fossil fuels to generate electricity to hydrolyze water is at least one stage of inefficiency too many given that refineries routinely use steam reforming methods to make it directly from feedstock.
But the goal is to produce zero-carbon hydrogen, which as I understand it can only come from renewables or nuclear. Not simply as a transportation fuel but also to replace coke in steelmaking. Just looks like we are a zillion miles away from this at present.
We looked at a solar powered hydrolyzer many years ago. It was supposed to be able to power a remote communication relay. The idea was solar in the day, and excess power to make hydrogen that would power a fuel cell overnight. The scale was never there. It wasn't even close. After doing the basic math we walked on the whole concept (we did do solar to supplement battery and generator). That was one of the projects that led me to the belief that the only green future we have is the one that glows. Wind, solar, hydro and conservation are all important components, but there is no true solution to our energy needs without nuclear. Small, standardized, distributed, reactors. Without nuclear, we don't make it to the place where we quit burning dinosaurs. And until we stop doing that, we are just wandering down the path to oblivion (but our cell phones will be fully charged).
Doesn't look like much has changed in the meantime. I remember getting excited about fuel cells 30 years ago, which never made a breakthrough for much the same reasons.
ok, these guys just won an Earthshot prize for this electrolyzer, which got me curious.
Can someone check my math on this?
(schnipp)
Thanks for this! Still want to do some math myself.
But do you happen to know if they actually did something new?
The are some thoughts about storing wind energy as H2 to secure energy supply. OK. If you want an uninterrupted supply of 1 wind turbine then, assuming for ease of the calculation that a wind turbine normally only produces 33% of the time (it is a little bit higher than 33% but definitively less than 50%), then you will need 3 turbines if you discard any conversion losses. This extra production has to be stored and batteries are not a real option.
Now factor in conversion losses. Electricity from the turbine -> some synthetic fuel (H2?) -> burn -> electricity. If each step is 90% efficient (quite good) then we have 73%. With 80% (still good) it is 52%. However H2 has its issues so let us convert it to an easy simple fuel (for storage and transport) like gasoline, diesel, or kerosine which you can store as a liquid (e.g. in a simple jerrycan). So an additional step. With 90% you will find 65% overall, and 80% gives 40%. With 90% efficiency the 2 extra turbines require 1 extra turbine, with 80% you will need 3 extra wind turbines. So to secure long term energy of 1 wind turbine you will need 4 to 6 wind turbines. If you don't want the extra turbines (or nowhere to put them), then what do you use? Gas turbines ... (you can switch them on and off when needed, somehow I am not so keen on nuclear).
Sorry but I get horror visions of the north sea (with devastating effects because of the noise for sea life (whales, dolphins), and migrating birds) or landscapes (birds of prey look downward, there was this rare bearded vulture who wandered into the Netherlands who was chopped in half in May).
Agreed that burning fossil fuels to generate electricity to hydrolyze water is at least one stage of inefficiency too many given that refineries routinely use steam reforming methods to make it directly from feedstock.
But the goal is to produce zero-carbon hydrogen, which as I understand it can only come from renewables or nuclear. Not simply as a transportation fuel but also to replace coke in steelmaking. Just looks like we are a zillion miles away from this at present.
We looked at a solar powered hydrolyzer many years ago. It was supposed to be able to power a remote communication relay. The idea was solar in the day, and excess power to make hydrogen that would power a fuel cell overnight. The scale was never there. It wasn't even close. After doing the basic math we walked on the whole concept (we did do solar to supplement battery and generator). That was one of the projects that led me to the belief that the only green future we have is the one that glows. Wind, solar, hydro and conservation are all important components, but there is no true solution to our energy needs without nuclear. Small, standardized, distributed, reactors. Without nuclear, we don't make it to the place where we quit burning dinosaurs. And until we stop doing that, we are just wandering down the path to oblivion (but our cell phones will be fully charged).
It's also driven by scientific illiteracy, the same kind that makes people believe in 200 mpg carburetors and perpetual motion machines.
Making hydrogen from fossil fuels may actually be more efficient than burning said fuels to generate electricity and using that to hydrolyze water*.
*Haven't checked, don't care, don't need three decimal places on dumb idea.
Agreed that burning fossil fuels to generate electricity to hydrolyze water is at least one stage of inefficiency too many given that refineries routinely use steam reforming methods to make it directly from feedstock.
But the goal is to produce zero-carbon hydrogen, which as I understand it can only come from renewables or nuclear. Not simply as a transportation fuel but also to replace coke in steelmaking. Just looks like we are a zillion miles away from this at present.
I suspect the desire to replace fossil fuels with hydrogen is driven more by public pressure than common sense, as the largest supplier of hydrogen will be the oil companies. Then again, maybe further down the road the transition will end up making sense from an ecological perspective once production of hydrogen from renewable energy ramps up and the infrastructure is already in place. Still not quite sure what to make of it.
It's also driven by scientific illiteracy, the same kind that makes people believe in 200 mpg carburetors and perpetual motion machines.
Making hydrogen from fossil fuels may actually be more efficient than burning said fuels to generate electricity and using that to hydrolyze water*.
*Haven't checked, don't care, don't need three decimal places on dumb idea.
On a mass basis H2 is high energy density. On a volume basis much lower than liquid fuelsâhence the enormous external tank on the H2/O2 powered space shuttle.
I suspect the desire to replace fossil fuels with hydrogen is driven more by public pressure than common sense, as the largest supplier of hydrogen will be the oil companies. Then again, maybe further down the road the transition will end up making sense from an ecological perspective once production of hydrogen from renewable energy ramps up and the infrastructure is already in place. Still not quite sure what to make of it.
thought it might be. Thx for the feedback.
H2 is still getting hyped here quite a bit. Mostly for industrial applications needing high energy density fuels.
On a mass basis H2 is high energy density. On a volume basis much lower than liquid fuels—hence the enormous external tank on the H2/O2 powered space shuttle.
Yes, hydrogen is basically a very inefficient battery. Its appeal lies in its portability: if you have a source of electricity that isn't doing anything else you can turn it into stored energy that you can burn in modified current technology.
It will still have emissions issues as long as you're burning it in a conventional IC engine breathing an atmosphere that's mostly nitrogen, but they are way down from fossil fuels. They're also way down on powerâBMW has been shipping hydrogen powered cars for years, and compared to the same model gasoline engine they make significantly less power.
But it's no breakthru technology. Kind of a dead end.
thought it might be. Thx for the feedback.
H2 is still getting hyped here quite a bit. Mostly for industrial applications needing high energy density fuels.
ok, these guys just won an Earthshot prize for this electrolyzer, which got me curious.
Can someone check my math on this?
According to the data sheet, it needs 2400Wh to produce 500 normal litres of hydrogen
Apparently it takes 11,200 litres (11.2 m^3) of hydrogen to come up with 1kg of hydrogen at normal pressure, which this machine would produce in about a day's uninterrupted operation (500 x 24 = 12000 litres). How does this tally with the data sheet which states 4.8 kWh for 1m^3 of hydrogen? It seems to be out by a factor of roughly 10.
Whatever, hydrogen has a usable energy density of 33.6 kW per kg, so this machine is producing roughly 33.6 kW of energy in one day from 57.6 kW of electricity as an input, plus the water.
One electrolyzer costs â¬9000.
So, assuming the above is correct, the question is what other infrastructure would you need? And what would be the total cost of generating enough fuel to run a hydrogen-powered car at say 12000 km/year ignoring the cost of the car?
According to the manufacturer, the BMW i3 consumes 15.3 kWh for 100 km, so, assuming a hydrogen-powered car were similarly efficient (probably not), you could produce enough hydrogen to power a car for 200 km, (based on 24 hour production).
hmm.. so what are the pitfalls?
Cost of power: our local price for renewable electricity is 30c per kWh which translates into â¬14 a day to power the electrolyzer.
I guess you could source the power from small wind-turbines but this is variable - only on windy days, etc. or PV
Storing the hydrogen
Dangers of hydrogen
And what is the true energy balance on inputs (manufacture of the infrastructure etc. compared to the output?
Welcome to the laws of thermodynamics!
Yes, hydrogen is basically a very inefficient battery. Its appeal lies in its portability: if you have a source of electricity that isn't doing anything else you can turn it into stored energy that you can burn in modified current technology.
It will still have emissions issues as long as you're burning it in a conventional IC engine breathing an atmosphere that's mostly nitrogen, but they are way down from fossil fuels. They're also way down on power—BMW has been shipping hydrogen powered cars for years, and compared to the same model gasoline engine they make significantly less power.
But it's no breakthru technology. Kind of a dead end.
ok, these guys just won an Earthshot prize for this electrolyzer, which got me curious.
Can someone check my math on this?
According to the data sheet, it needs 2400Wh to produce 500 normal litres of hydrogen
Apparently it takes 11,200 litres (11.2 m^3) of hydrogen to come up with 1kg of hydrogen at normal pressure, which this machine would produce in about a day's uninterrupted operation (500 x 24 = 12000 litres). How does this tally with the data sheet which states 4.8 kWh for 1m^3 of hydrogen? It seems to be out by a factor of roughly 10.
Whatever, hydrogen has a usable energy density of 33.6 kW per kg, so this machine is producing roughly 33.6 kW of energy in one day from 57.6 kW of electricity as an input, plus the water.
One electrolyzer costs €9000. So, assuming the above is correct, the question is what other infrastructure would you need? And what would be the total cost of generating enough fuel to run a hydrogen-powered car at say 12000 km/year ignoring the cost of the car?
According to the manufacturer, the BMW i3 consumes 15.3 kWh for 100 km, so, assuming a hydrogen-powered car were similarly efficient (probably not), you could produce enough hydrogen to power a car for 200 km, (based on 24 hour production).
hmm.. so what are the pitfalls?
Cost of power: our local price for renewable electricity is 30c per kWh which translates into €14 a day to power the electrolyzer.
I guess you could source the power from small wind-turbines but this is variable - only on windy days, etc. or PV
Storing the hydrogen
Dangers of hydrogen
And what is the true energy balance on inputs (manufacture of the infrastructure etc. compared to the output?
Texas wind turbines freeze as Texas orders rolling black outs
Huh!?!!
Should we Canadians order care packages of white lithium grease and send them to Texas? Or do Texans need lessons in risk management?
I would really like somebody familiar with the technology of these wind turbines to explain to me how they managed to freeze. I do not recall wind turbines in cold oceans such as the North Atlantic freezing.
Apparently, wind turbines used in predictably-coldlocations can have heating systems installed in them for their gearboxes and other components. The present temperatures in many parts of Texas are well below normal ranges for those areas, such an idea may never have come up for them.
Thanks Proclivities. The Natural Resource Canada ministry website is informative. I have learned a lot about wind turbines and Texas grid management over the past couple of days.
I gather that wind turbines can be cold weather-proofed like just about everything else.
Some US pundits appear to have a negative view of Texas management. According to Julian Lee at bloomberg.com, Texan politicians may be blaming green energy but apparently conventional sources were impacted even harder. Blame Texas Exceptionalism For This Crisis, Not Green Energy - Julian Lee, Bloomberg Itâs time the state prepared its power supply for more cold winters.
Two reflections:
1. Given the numbers I am hearing/reading, Texas did a bad job of risk management. People died.
2. When are supposedly educated, bright Americans going to take anthropogenic climate disruption seriously?
Texas wind turbines freeze as Texas orders rolling black outs
Huh!?!!
Should we Canadians order care packages of white lithium grease and send them to Texas? Or do Texans need lessons in risk management?
I would really like somebody familiar with the technology of these wind turbines to explain to me how they managed to freeze. I do not recall wind turbines in cold oceans such as the North Atlantic freezing.
Apparently, wind turbines used in predictably-coldlocations can have heating systems installed in them for their gearboxes and other components. The present temperatures in many parts of Texas are well below normal ranges for those areas, such an idea may never have come up for them.
