Will Solar Power Outshine Oil in the Near Future?

In summary, the ad does not provide enough information to say whether or not this technology exists and if it does, whether or not it would be cost-effective.
  • #141
nitsuj said:
Would we have gone to the moon on Investor capital? Or create all those inventions as a result? What about military? This is how the economy works, sometimes the gov money is needed to "push" a tech up and over into being economically viable for investment...so now it is...yay to circumnavigating investor nearsightedness.

Was nuclear brought to fruition on venture capital?
You switched from "solar power is so cheap!" to "we should subsidize it, so it might become viable in the future"?

How much tax money should we put into solar power, and how much will solar power cost in the future?
Germany alone invested more than $100 billions for direct subsidies (for power delivered to the grid) already, and commited to pay $150 to $200 billions more in the next 25 years (depending on how much gets installed in the next years). Add various other subsidies and we get a big three-digit billion number. And that is just Germany, many countries have subsidies.

Compare this to fusion, for example. The international community struggles to find $1-2 billions per year for ITER, and total US funding over the last decades is somewhere below $20 billions (in today's dollars).
mheslep said:
When it comes to the scale of the energy industry, I don't think 1 MW pilot plants (most are smaller) in Germany qualify as 'getting there' as opposed to propaganda stage props for Energiewende.
I mean "getting there" in terms of overproduction. Negative market prices are getting common.
 
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  • #142
NTL2009 said:
Solar PV has already been brought to you by the government military/space program. It is now in the hands of the market to improve value.

That's silly; you've already made the point it is not yet economically viable without subsidies. Should clean energy production sit stagnant? I don't think so, I want to see it turbo'd with everyone's contribution.

Now get me one of those NASA miniature Nuclear or RTG power plants!
 
  • #143
nitsuj said:
I cannot subscribe that the ontario PV industry subsidies will retard the progress of PV tech. I would argue that those subsidies have grown to a great extent the current PV industry in Ontario...More panels, batts and jobs.

If I have old panels that make x amount, why would this stop progress towards a even better pay back? PV is not a trivial thing like a can opener.
Because as I said, it reduces motivation for better panels.

An analogy - think back to when a laptop computer was a big, heavy, short battery life, small screen 'lug-able' device. They were expensive, and not a very good value proposition, other than for people who really needed portability, even if it meant it was 'lug-able'.

But manufacturers knew they could increase sales as they improved the value - making them smaller, lighter, cheaper. So they worked very hard at it.

Now consider an alternate universe where the government decided to subsidize lug-able computers, to grow the market. We will use an extreme case to illustrate, but assume the subsidy was so great, that people bought them even if they didn't have a great need for portability. The manufacturers could sell all they could make. They had no motivation to improve them, they had a market, provided by the government subsidy. So advancements were not as fast as when those companies had to improve the product to increase sales.

Personally, I'd be thrilled to buy into a solar farm, if the numbers would work. But I still feel that solar has to come down in price to offset the risks to my investment.
 
  • #144
mfb said:
You switched from "solar power is so cheap!" to "we should subsidize it, so it might become viable in the future"?

Generating power with solar is "so cheap", compared to those requiring maintenance, infrastructure. We should subsidized it to compete, from an installation perspective, with the Multi billion dollar head start that traditional means has over solar.

The are a silly amount of in-calculable costs associated with traditional power generation.

Show me one instance of a purely venture capital funded nuclear power plant.
 
  • #145
NTL2009 said:
I'm curious as to how this is determined
Several factors include curtailment of wind and solar (throwing away extra, i.e no return) and the marginal cost or running dispatchable power plants (ie gas) that *must* be in the grid without storage.

Wind for instance devalues to about 85% of its original value at 10% grid share. Solar devalues much faster.
Wind_Solar_p2_4.png
https://thebreakthrough.org/index.php/voices/energetics/a-look-at-wind-and-solar-part-2
 
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  • #146
nitsuj said:
That's silly; you've already made the point it is not yet economically viable without subsidies. Should clean energy production sit stagnant? I don't think so, I want to see it turbo'd with everyone's contribution. ...

First, I do not accept that sales subsidies can "make or not make anything economically viable". A thing is economically viable or it isn't, based on cost versus what it produces/saves. A sales subsidy only changes who is paying for it, and that's a political decision, not physics or economics.

Why do you ask me if I think clean energy production should sit stagnant? Re-read my posts, I've said there is far better use for money to promote green energy than sales subsidies. I say that anyone who wants to promote clean energy should be against sales subsidies, and for more effective means of bringing clean energy on line.

And it isn't always a measure of pure, hard $. We might decide, as a nation or community, that it is OK to run a solar farm at a loss if we need to, because we feel (and hopefully can back it up with reasonable numbers), that the pollution reduction is worth the $ cost. Fine, then let's do it. But then just let the taxpayers share in funding that solar farm (and share in benefits if it is economically viable), which as we've determined can be installed far cheaper than individual rooftop solar, rather than providing a subsidy to an individual, who maybe benefits personally with reduced electrical costs, at other's expense. And since that residential rooftop solar is unlikely to be as well placed as a solar farm, the taxpayer gets less green energy for their $. It's lose-lose for everyone. We should just stop it!
 
  • #147
NTL2009 said:
Because as I said, it reduces motivation for better panels.

An analogy - think back to when a laptop computer was a big, heavy, short battery life, small screen 'lug-able' device. They were expensive, and not a very good value proposition, other than for people who really needed portability, even if it meant it was 'lug-able'.

But manufacturers knew they could increase sales as they improved the value - making them smaller, lighter, cheaper. So they worked very hard at it.

Now consider an alternate universe where the government decided to subsidize lug-able computers, to grow the market. We will use an extreme case to illustrate, but assume the subsidy was so great, that people bought them even if they didn't have a great need for portability. The manufacturers could sell all they could make. They had no motivation to improve them, they had a market, provided by the government subsidy. So advancements were not as fast as when those companies had to improve the product to increase sales.

Personally, I'd be thrilled to buy into a solar farm, if the numbers would work. But I still feel that solar has to come down in price to offset the risks to my investment.

Today the thin laptops are more expensive than the thicker ones, both continue to improve. early adopters are always a thing.

I don't know what motivation means if not "increasingly better PV's systems".

It's a profit / square foot thing driving the innovation.
 
  • #148
nitsuj said:
Show me one instance of a purely venture capital funded nuclear power plant
All of the nuclear reactors just finished (Watts Bar II) or under construction (Vogtle 3, 4 and Virgil 2, 3) in the US were funded by their owners, either private or local municipalities, as is done with other power plants. See here for Vogtle. The US government funds general research on all kinds of energy technology, including nuclear. The US government also offered to *guarantee* the private loans to Vogtle and Virgil, incurring some risk to the treasury, but this has so far inccurred no cost to the taxpayers. This has been the model for most (if not all) of existing US nuclear reactors. All US nuclear operators also i)pay for private insurance and ii) pay into a trust which funds eventual decommisioning and a waste depot.
 
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  • #149
NTL2009 said:
First, I do not accept that sales subsidies can "make or not make anything economically viable". A thing is economically viable or it isn't, based on cost versus what it produces/saves. A sales subsidy only changes who is paying for it, and that's a political decision, not physics or economics.

?? What ever you want to call it at the end of the day, government intervention can sway the invisible hand; clearly.
 
  • #150
nitsuj said:
?? What ever you want to call it at the end of the day, government intervention can sway the invisible hand; clearly.
But often not in the right direction.
 
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  • #151
NTL2009 said:
But often not in the right direction.

This is why we each get one vote.
 
  • #152
NTL2009 said:
Why don't you answer the question? It was a simple question - if you net to zero for the year, what would your bill be?

Example for 1000kwhrs/month with a net meter reading of zero. I break the day roughly into two parts for this example one when he supplies power to the grid and himself and the other when he takes power from the grid.

He uses in one day an average of 33.3 kwhrs . for an average use of 1.4 kwhrs/day. HIs panels produce power non uniformly over the part of the day with the most sun say from 8am to 4pm i.e. 8 hrs. when he uses 11.2 kwhrs. leaving him excess power to sell back to the utility. The rest of the day (16 hrs) he draws from the grid 22.4 kwhrs (1.4x16). What is the power of his panels to get a net reading of zero? About 4.2 kw. On a good day he will sell back to the utility 22.4 kwhrs. A use rate of $0.15/ kwhr is reasonable. He gets paid for the excess power at a wholesale price of $0.05/kwhr.a number which I saw on the web.

At the end of the day his utility charge is $0.15x22.4 = $3.36 or $1226/yr of which $613 is the transmission charge.
He will receive a annual payment for the excess power of $ 0.05x22.4x365 = $ 408

His net yearly cost for electrical service is $818

A non solar neighbor with the same use pays $1823

Our net saving is $1005/year

You are ahead $1005 per year (including payback from power generated) toward the amortization of you solar system which cost you $11,340 including the investment tax credit but not including financing costs.

Currently home equity loans are about 4.5% and a ten year loan of $11,340 would cost about $118 per month so the cost of financing is about $2,790.

Your total financial commitment for the solar installation is about $14,130 which you are amortizing at a rate of $1005 per year from you power savings
You are in the black in about 14 yrs. Also note for the first 10 years this project cost and additional $34 a month more out of your household budget and after 14years you are finally putting that $1005 savings in the bank.

Hope I got the numbers right>
 
  • #153
nitsuj said:
This is why we each get one vote.
Yes, but people who understand technology and economics should be pointing out the fallacies and pros/cons to those who don't.

Many, many voters are ignorant on these matters. 'Feeling' that something is the right thing to do doesn't make it the right thing to do. I'd like to educate voters on how to get the most real benefit for our tax dollars. Shell games don't cut it.
 
  • #154
nitsuj said:
Should clean energy production sit stagnant? I don't think so, I want to see it turbo'd with everyone's contribution.
I don't think so either, but that still leaves the question which type of clean energy to choose. Nuclear power doesn't need the hundreds of billions of subsidies solar power is getting.

Take the ~$300 billion estimate of German subsidies from above (which is probably too low), and nikkom's reference for nuclear power, and you can install 50 GW, for an average production of ~45 GW. That is 2/3 the total German electricity consumption. But the best thing: You don't even have to spend that money. You just have to permit the construction of new nuclear power plants, they will pay for themselves.

Fund R&D for solar power: Yes, certainly. It will be interesting to see how cheap it can get, and it might become commercially interesting without subsidies in the future.
Fund the installation of current panels: Please don't.
 
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  • #155
nitsuj said:
Should clean energy production sit stagnant?
It's not. Some 60 commercial nuclear power reactors are currently under construction globally in a dozen different countries. A dozen next generation nuclear technology companies have recently started, one of them heavily funded by Bill Gates. The number of new reactors could easily be double, triple, if not for the anti-nuclear noise from the like of David 'I got to a gun' Crosby and his doppelgangers in other countries.
 
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  • #156
gleem said:
A use rate of $0.15/ kwhr is reasonable
No. The utility may make that marginal power at $0.02/kWh, night or day, winter or summer. This is the problem with the net metering rules, forcing the utility to pay retail for power dumped on the grid.
 
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  • #158
gleem said:
A use rate of $0.15/ kwhr is reasonable

mheslep said:
No. The utility may make that marginal power at $0.02/kWh, night or day, winter or summer. This is the problem with the net metering rules, forcing the utility to pay retail for power dumped on the grid.
I currently pay $ 0.15/kwhr which compared to the nation seem to be in the middle.

https://www.electricchoice.com/electricity-prices-by-state/
 
  • #159
gleem said:
I currently pay $ 0.15/kwhr which compared to the nation seem to be in the middle.

https://www.electricchoice.com/electricity-prices-by-state/
You are making a similar mistake as I did earlier: the only thing you save the utility by not drawing a kWh is the cost of generating it. When you credit back to solar users the cost of running an electrical grid, you are making everyone else pay twice for it.

Indeed, It's even a little worse than that for net metering because in effect the solar provider is CHARGING the utility to use its wires instead of PAYING the utility to use its wires!
 
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  • #160
nitsuj said:
Generating power with solar is "so cheap", compared to those requiring maintenance, infrastructure. We should subsidized it to compete, from an installation perspective, with the Multi billion dollar head start that traditional means has over solar.
That first sentence is self-contradictory, but I don't understand why you are even trying to make this argument. You can be a fan of solar and support a crash program entirely US government funded to build a 100 mile squared solar farm in the western desert or a government provided solar roof for every building if you want. It's fine if you want that! Everyone gets to decide for themselves what "should" be done.

We all want basically the same thing; the cleanest, safest, cheapest energy we can get...though not necessarily in order of emphasis.

But what you/we can't have is to believe that market forces want any particular plan. They don't necessarily support the one we want. and that's ok too if we make the choice with our eyes open.

My personal fantasy (as outlined in my now 13 year old energy thread in General Engineering) starts at the same place @mfb's does and leads in a similar direction: the hundreds of billions of dollars of government money spent on solar power in the past couple of decades has been inefficiently spent. If we instead directed those incentives toward nuclear power - along with legislation to cut through the red tape - we could have a coal-free grid right now. We just have to choose to do it, as France did. I recognize that because that plan includes the word "subsidy", it is not a strictly capitalist solution. That's fine! I still want it!

The path we've been on for the past few decades and remain on today will not get us a clean grid any time in the forseeable future. How much more time/money are we going to waste on this path?

Caveat: the current path of penalizing coal and incentivizing solar may get us to a mostly natural gas fueled grid, but that isn't going to be good enough and most environmentalists don't actually support that result.
 
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  • #161
gleem said:
NTL2009 said:
Why don't you answer the question? It was a simple question - if you net to zero for the year, what would your bill be?
Example for 1000kwhrs/month with a net meter reading of zero. I break the day roughly into two parts ...

Hope I got the numbers right>
I didn't check the numbers yet, but I will first note that regardless, everything hinges on this statement:

He gets paid for the excess power at a wholesale price of $0.05/kwhr. a number which I saw on the web.
... his utility charge is $0.15 ...
Does he get charged $0.15 and gets paid $.05? Most of the references I've seen "on the web" talk about the "meter running backwards" and a 1:1 offset (IOW, getting paid full retail including distribution for power generated).

From the link russ_watters supplied earlier:
http://www.eei.org/issuesandpolicy/generation/NetMetering/Documents/Straight%20Talk%20About%20Net%20Metering.pdf
While net metering policies vary by state, customers with rooftop solar or other DG systems usually are credited at the full retail electric rate for any excess electricity they generate and sell to their local electric utility via the electric grid. Electric utilities are required to buy this power, even though it generally would cost them less to produce the electricity themselves or to buy the power on the wholesale market from other electricity providers.
It sounds like this may be changing in the future, but it can't just be monitored at the meter, they will need to tap into your panels to know how much is produced/offset. Otherwise, the amount of consumption while the panels are producing won't be charged. They wouldn't know if the lower kWh during a day was because the panels offset some consumption, or if you simply had lower consumption.

Or do the different charges only apply to excess generation? Excess for the month, or excess at any time? Details!

You are in the black in about 14 yrs. Also note for the first 10 years this project cost and additional $34 a month more out of your household budget and after 14years you are finally putting that $1005 savings in the bank.
If those numbers are correct, 14 years just isn't very appealing to me.
 
  • #162
NTL2009 said:
I recall reading a good article recently - they said that if we are going to have sales subsidies on solar PV, it should be based not on the cost of the installation, but on the energy produced.
There's an old saw about fire wood... "it heats you twice -- once when you cut it, and once when you burn it" ...

During a Mont. winter I've seen it snow, at least a little, every day for weeks. Can a 245 pound guy walk on photovoltaic modules?
If these were included in the installation package, I'll bet I wouldn't need any other form of heater at all...[COLOR=#black].[/COLOR] :oldcool:

Scoop1.jpg

BTW, our experience with PV battery chargers for electric fencing has been... well, somewhat disappointing.
 
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  • #163
mheslep said:
Several factors include curtailment of wind and solar (throwing away extra, i.e no return) and the marginal cost or running dispatchable power plants (ie gas) that *must* be in the grid without storage.

Wind for instance devalues to about 85% of its original value at 10% grid share. Solar devalues much faster.
View attachment 204029https://thebreakthrough.org/index.php/voices/energetics/a-look-at-wind-and-solar-part-2
This is telling me that as we get more and more solar PV, it has to be come cheaper just to keep up.

Getting to ~ 4% solar from where we are now (sub 1%?) means you might get ~ 75% of the income you would expect today.
 
  • #164
mheslep said:
You proposed leaving all the "existing power plants intact", i.e. the coal and gas plants (fueled instead by hydrogen). That's one.
Which is already in place.
Then you would build another power generation system of comparable size based on solar and wind. That's two.
Which is already happening: people are building wind and solar farms. They are increasing in number incrementally.

Money currently being spent on temporary mining operations that have to be shifted to other places when the supply runs dry, could, instead, be put into permanently placed hydrogen farms. This isn't a new "grid." The "grid," here, if you insist on using the term to refer to something other than the electrical grid, would be the gas transport pipe system. The operative change is a shift from fossil mining to hydrogen farming. A hydrogen farm at a fixed location would represent a stable business with stable jobs. I see it as a business that produces fuel with the primary customer being the existing utilities. As it is, that business, currently producing natural gas rather than hydrogen, now constantly shifts location, starting from scratch at each new site, which is the kind of expense a fixed hydrogen farm wouldn't have. It is a shift over time, and not the building of a completely separate system that would co-exist with the first. At the end of the process it would be all hydrogen and no more natural gas (or coal).
Also, a gas storage system is required, large enough to supply a nation for a month or so.
Also built up incrementally over time. (And I don't see any reason to stop at a month's supply.)
BTW, the pipelines in place to transport natural gas (hundreds of thousands of miles) have some H2 mixed in but can be wholly converted to hydrogen. H2 would leak where CH4 won't, embrittles pipes not designed for it...
I'd like a source for H2 leaking and embrittling pipes. Assuming you have them, these are your best objections. They mean the natural gas pipeline system would have to be replaced incrementally over time.
and has a lower volumetric energy density than methane requiring a larger pipe diameter to ship energy at the same rate.
Or, being so much less massive, it could be put through the same pipes more quickly. I don't know, but I question your apparent assumption the only possible solution is larger diameter pipes.

Natural gas accounts for a little over 30% of US electricity now, right? At some point in the past, there was no system in place for natural gas but over time it got built. In the same way a system for hydrogen transport can replace it. Cumulatively, the current natural gas transport system cost a lot of money, and someone could have objected to the concept at the outset based on that: "You're proposing a whole new grid on top of coal! Too expensive!" Which seems to me like what you're doing. No natural gas well produces forever, therefore the natural gas pipe system is already constantly being reworked as some sites stop producing and new ones are added. How much of the existing hundreds of thousands of miles of pipe system is authentically "arterial," so to speak, intended to be as permanent as possible, and how much is temporary capillary, only intended to last as long as a given well, or group of wells, continues producing?
 
  • #165
NTL2009 said:
Does he get charged $0.15 and gets paid $.05? Most of the references I've seen "on the web" talk about the "meter running backwards" and a 1:1 offset (IOW, getting paid full retail including distribution for power generated).

The example I gave was without net metering where the utility monitors measures how much you use separately from how much you provide and charges/pays accordingly. This would seem to be a more logical method The Net Metering is suppose to allow people who generate their power to be able to use its excess energy at a future time. Thus if someone with a 7Kw installation generates 35 Kwhrs of energy the net metering program allow the user access to the excess power at a later time just as if he stored it. The net result is that the utility "buys" the power from him at the retail rate sells it to someone else.when the original user need power he get it back free.. So it make the utility a virtual battery. The utility takes a hit with this system. However it is my understanding that this is done on a contractual basis which may contain other rules and I don't think the utilities are not somehow recouping this money aside from cost shifting.Utilities are suppose to obtain a percentage of their energy from renewable sources eg BG&E in Mayrland it is 20% but they are only permitting 2% to be residential solar and it is the only viable renewable energy source for the majority of residential properties.
 
  • #166
Hydrogen production by electrolysis using solar cells on an economical commercial scale is a heck of a lot harder than I suspected and currently isn't quite there yet. see https://www.nature.com/articles/ncomms13237
 
  • #167
russ_watters said:
If we instead directed those incentives toward nuclear power - along with legislation to cut through the red tape - we could have a coal-free grid right now. We just have to choose to do it, as France did. I recognize that because that plan includes the word "subsidy", it is not a strictly capitalist solution. That's fine! I still want it!
I disagree. Nuclear technology does not need subsidies; that is, funding by the taxpayer. See, e.g., the O&M cost of existing nuclear, built in the late 70s, at $0.015/kWh. That plant regularly bids into the next-day PJM market at $0/MWh, knowing that any other source has to bid higher and locks in a higher price for all the bidders. Only hydro and geothermal compete when available, and no other source has any near term path to becoming competitive.

Nuclear in the US simply needs the NRC to attend to reasonable safety and reasonable approval. It otherwise needs get out of the way, to stop, in effect, demanding nuclear be long to build and expensive, locking in their role and the revenue of the *existing* power fleet in the US. Examples of needless getting in the way would be i) NRC/DoE testimony stating it will only approve light water reactors, because of all the people currently working in light water, and ii) NRC imposition of new requirements on a nuclear power plant already licensed/approved and under construction.

Applying subsidies to nuclear as-is will in effect lock in the current dysfunction; that is, lock in high costs which will prevent large scale adoption of nuclear by developing countries, the key to global adoption of clean power.
 
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  • #168
  • #169
mheslep said:
I disagree. Nuclear technology does not need subsidies; that is, funding by the taxpayer...

Only hydro and geothermal compete when available, and no other source has any near term path to becoming competitive.

Nuclear in the US simply needs the NRC to attend to reasonable safety and reasonable approval. It otherwise needs get out of the way, to stop, in effect, demanding nuclear be long to build and expensive, locking in their role and the revenue of the *existing* power fleet in the US. Applying subsidies to nuclear as-is will in effect lock in the current dysfunction; that is, lock in high costs which will prevent large scale adoption of nuclear by developing countries, the key to global adoption of clean power.
It is tough to say since I haven't seen "getting out of the way" so I don't know what it looks like, but I think what you are saying only applies to how we got where we are today. Moving forward, I don't think market forces would work fast enough to get all of the existing coal plants closed (losing their construction costs) and new nuclear plants built in their place quickly. Maybe by enhancing the punishment of coal power production, but that's similar to an incentive for other sources.

Either way, I would definitely want a subsidy to come along with a policy of getting out of the way and would think the two would go hand in hand (though I recognize the government can screw anything up).
 
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  • #170
gleem said:
Hydrogen production by electrolysis using solar cells on an economical commercial scale is a heck of a lot harder than I suspected and currently isn't quite there yet. see https://www.nature.com/articles/ncomms13237

However, the cost of H2 produced by electrolysis is still significantly higher than that produced by fossil fuels. The Department of Energy has calculated the H2 threshold cost to be $2.00–$4.00 per gallon of gasoline equivalent9, whereas the most up-to-date reported H2 production cost via electrolysis is $3.26–$6.62 per gallon of gasoline equivalent10.

The paper is about the efficiency of conversion of sunlight to hydrogen, but I find this part the most damning:

Some amount of H2 is equivalent to a gallon of gas. Paying $2-$4 for that amount of hydrogen is the "threshold for viability", meaning, I assume, if the utility can pay that amount of money for that amount of hydrogen, it becomes viable for them to purchase it.

However, the current cost to produce that amount of H2 is actually $3.26-$6.62. Which makes it non-competitive.

I wonder how they are calculating this cost, and where, other than more efficient conversion, it can be cut.
 
  • #171
russ_watters said:
It is tough to say since I haven't seen "getting out of the way" so I don't know what it looks like,
Chinese, S. Korean nuclear. About a third the cost, built in half the time. Labor costs explain only a small piece of the difference. Edit: in other industries, see the 1978 deregulation of the airlines, the deregulation of the radio spectrum leading to auctions, and even the fire code changes that originally prevented http://www.nacsonline.com/magazine/pastissues/2011/october2011/pages/feature8.aspx

"Most state laws had provisions that forbade self-serve dispensers in service stations," said Bob Benedetti, who is responsible for the flammable liquids code project for the National Fire Protection Association.

Gradually, 48 states changed the fire codes to allow for self-service dispensers. "Some thought there would be an increase in the incidence of accidents or fires at service stations with self-service dispensers, but that never materialized," said Benedetti.
russ_watters said:
...Moving forward, I don't think market forces would work fast enough to get all of the existing coal closed (losing their construction costs) and new nuclear plants built in their place quickly.
Well, see the rate of coal displacement by cheap gas plants in the US as an illustrative example. I don't have handy how much coal plant capacity has retired, but about https://grist.files.wordpress.com/2010/08/ceres-us_electric_generating_capacity_by_in_service_year.jpgwhile national demand increased slightly. I think it would go much faster but for the caution by investors/utilities that currently cheap gas might increase in price in ~20 years. That's not a problem with nuclear fuel.

russ_watters said:
Either way, I would definitely want a subsidy to come along with a policy of getting out of the way and would think the two would go hand in hand (though I recognize the government can screw anything up).
Subsidies encourage corruption (as they are set by politicians which benefit the few), and work against the efficiency of the market looking for the best deal. The forces behind them are are some of the worst aspects of our republican system: the sugar subsidy, the ridiculous periodic dance politicians do in Iowa for the corn subsidy, etc. Not only do subsides increase cost, they create incentives to continue that which is commonly known to be in excess, like sugar. Perhaps subsidies are occasionally necessary, but I would have them as last resort. An across-the-board tax on the that which is undesirable is definitely more efficient than subsidies that pick winners, though it has the downside of losing to foreign (un-taxed) competition in the presence of trade.
 
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  • #172
zoobyshoe said:
The paper is about the efficiency of conversion of sunlight to hydrogen, but I find this part the most damning:

Some amount of H2 is equivalent to a gallon of gas. Paying $2-$4 for that amount of hydrogen is the "threshold for viability", meaning, I assume, if the utility can pay that amount of money for that amount of hydrogen, it becomes viable for them to purchase it.

However, the current cost to produce that amount of H2 is actually $3.26-$6.62. Which makes it non-competitive.

I wonder how they are calculating this cost, and where, other than more efficient conversion, it can be cut.
Regardless of the efficiency to produce the hydrogen, if we are burning it in a turbine to get the electricity back, those have something like 30%-40% efficiency, the CCGT maybe 60% (but these seem uncommon?). So you are losing half the power on the way out. If we lose half on the way in (just a guess), we are down to 25% recovery, far below pumped hydro (80's?). I'm not sure what assumptions to make to even take a stab at the math, but offhand it seems like the capital would need to be pretty cheap if it is only working part time and only recovers 25% of the excess.
 
  • #173
zoobyshoe said:
However, the current cost to produce that amount of H2 is actually $3.26-$6.62.
Most hydrogen (90%) is made from cracking methane, which currently costs about 13 cents per kg (1.5 m3) in the US.
 
  • #174
Distribution and handling of hydrogen, as differing from methane, is an extended subject. Again, some minority share hydrogen can theoretically be mixed into pipelines. Details:

zoobyshoe said:
Or, being so much less massive, it could be put through the same pipes more quickly. I don't know, but I question your apparent assumption the only possible solution is larger diameter pipes.
Not an assumption, physics. Mass is largely irrelevant to energy content flow in a gas pipeline. Velocity is proportional to the root of pipe diameter over the pipeline pressure loss, i.e. v = k√(D/H); D = pipe diameter, H = is pressure drop, k=constant. And so (page 21):

Because of the low volumetric energy density of hydrogen, the flow velocity must be increased by over three times. Consequently, the flow resistance is increased significantly, but the effect is partially compensated for by the lower viscosity of hydrogen. Still, for the same energy flow about 4.6 times more energy is needed to move hydrogen through the pipeline compared to natural gas

and from NREL, 2010:
http://www.nrel.gov/docs/fy13osti/51995.pdf
...Leakage
Hydrogen is more mobile than methane in many polymer materials, including the plastic pipes and elastomeric seals used in natural gas distribution systems. The permeation coefficient of hydrogen is higher through most elastomeric sealing materials than through plastic pipe materials. However, pipes have much larger surface areas than seals, so leaks through plastic pipe walls would account for the majority of gas losses (Appendix A). Permeation rates for hydrogen are about 4 to 5 times faster than for methane in typical polymer pipes used in the U.S. natural gas distribution system...

...Hydrogen Damage of Metals
Hydrogen damage is a form of environmentally assisted failure that results most often from the combined action of hydrogen and residual or applied tensile stress. The failure includes cracking, blistering, hydride formation and loss in tensile ductility and it has been generally called hydrogen embrittlement (ASM Vol. 13a). In general, the hydrogen damage occurs at a stress level below those typically experienced for a particular metal in an environment without hydrogen. It is affected by hydrogen pressure, purity, temperature, stress level, strain rate, and material microstructure and strength. The specific types of hydrogen damage have been categorized in ASM Handbook Vol. 13A, see Table 18.
 
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  • #175
NTL2009 said:
Regardless of the efficiency to produce the hydrogen, if we are burning it in a turbine to get the electricity back, those have something like 30%-40% efficiency, the CCGT maybe 60% (but these seem uncommon?). So you are losing half the power on the way out. If we lose half on the way in (just a guess), we are down to 25% recovery, far below pumped hydro (80's?). I'm not sure what assumptions to make to even take a stab at the math, but offhand it seems like the capital would need to be pretty cheap if it is only working part time and only recovers 25% of the excess.
I'm conceiving of a dedicated hydrogen farm whose sole function is to split water and then sell the hydrogen to utilities as opposed to an afterthought operation tacked onto a solar or wind farm that is designed to feed electrical power directly into the grid. I'm not thinking in terms of recovering excess. To split water you want high current, low voltage DC. In a dedicated hydrogen farm you engineer your windmills or PV to produce that. If you tack water splitting onto an operation designed to connect right to the grid, you'd have to transform the output electricity down and rectify it, which adds more equipment cost and losses. And the water splitting operation would always be under the constraint of not interfering with the main purpose, of always being on hold until "excess" was produced. I don't think it would get off the ground under those circumstances. Hydrogen would have to be treated as a product rather than a by-product to get developed in a timely way. That's how I'm thinking.

Anyway, Gleem's paper is disappointing because they were using current right out of the PV cells: none of the 'only 30%' efficiency is due to transformer or rectification losses.
 

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