Energy independence for the US (or any other country)

[Argentum Vulpes]

So it looks like any industrial process that consumer large amounts of energy should be powered by nuclear to save cost. Since it does not matter where in the world the manufacture is done how about we move all energy intensive production to say Chad and use nuclear?

So ship all of the worlds raw resources to Chad to be turned into products and then ship them back across the world? Need a skyscraper barge it back, need a bridge barge it back? If civilian nuclear power were used in the container ships then at least the current environmental impacts of current commercial shipping would be gone. But just think of the national security implications. Unless you are suggesting a one world government.

This is even more insane then using solar power centralized in the American south west as the power source for the USA.

 

[Skyhunter]

So these panels will be useless 89% of the time that they are out in operation. That looks like a colossal waste of resources, considering US nuclear power plants have a CF of 0.92.

I think we are talking about two different things.

And I am really not interested in derailing the thread with a debate about nuclear power.

 

[russ_watters]

That is your opinion and you are entitled to it.

I personally think it is a bit absolutist, but then that is just my opinion. Let's not derail the thread.

Well you are entitled to your opinion too, but the fact of the matter is that you didn't actually provide any proven solutions. You are hoping that the things you suggested could be viable, when we already know nuclear power is viable. Further, your ideas, at the very least, require time and money for research, mine does not and can be implimented now just by making the decision to do it. The French made that decision decades ago. The question that the OP asked is what can be done in the next 20 years and your idea simply could not be done in 20 years. Nuclear can.

Uranium is a limited resource. The nuclear plants of the future should be designed to burn the accumulated waste from older plants.

Certainly, it is limited, but it isn't as limited as most people think, partly due to the fraud that has been perpetrated on the American people when it comes to nuclear waste. For all intents and purposes, nuclear waste does not exist: http://online.wsj.com/article/SB123690627522614525.html

The Nanosolar started serial production of high efficiency, low cost thin film panels last year. They have two factories, one in San Jose and one in Germany. The one in Germany has a 640MW per year capacity.

Here is the http://www.nanosolar.com/sites/default/files/NanosolarCellWhitePaper.pdf"

That's nice but until it actually happens - until someone builds a commercial scale plant using their technology - it is still hypothetical.

A multi-faceted approach is IMO a better strategy.

Well I'm not saying we should get rid of hydro or stop building wind or even eliminate our natural gas. But I am of the opinion that a solution should be based on solutions. Since its inception, the environmentalist movement has always been based on hope and not reality. So for some four decades, while environmentalists have been wasting time hoping that this next big/new technology will have the ability to replace coal power, another country has already done it!

And now we have a President who'se primary campaign platform was "hope". So we've basically just formalized the policy of wasting time.

 

[Argentum Vulpes]

I think we are talking about two different things.

And I am really not interested in derailing the thread with a debate about nuclear power.

I do not see this as a derailing of the thread. The OP wanted to know what the best way to generate 50% of the USA or any other countries power from renewable sources. Even though it might be stretching the definition and conventional wisdom a bit about what classifies a renewable power source, nuclear power is a renewable power source. Or it is so darn close to one it might as well be one.

 

[russ_watters]

CF stands for Capacity Factor. It is a measure of how efficient something is at generating power. It is determined by dividing actual output with maximum output.

Efficiency isn't really the right word. It is more a measure of the fraction of time a plant is producing power at its nameplate capacity.

In other words (and I know you already know this part), a 1 MW nuclear plant with a 90% capacity factor produces 1*24*365*.9= 7884 MWh of energy per year while a 1 MW solar plant with an 11% capacity factor produces 1*24*365*.11= 964 MWh of energy a year.

In other words, assuming you can use the energy or store it, replacing 1 MW of capaicty from a high CF source like nuclear would require 8 MW of solar capacity.

 

[russ_watters]

No. The higher current and voltage eliminates the need for the extra cabling to the inverter. Since the panels themselves can carry the current, to the inverter. I didn't mean to imply that you could just plug it into a wall socket.

And this is something that really irritates me about a good fraction of the people in the "alternate energy" crowd. Ignorance of the technology helps drive the fantasy. Skyhunter, high voltage or not, a solar panel makes DC power, period. It requires an inverter to integrate it with the grid.

In addition, being "high voltage" is an irrelevancy because you can always just wire solar panels in series instead of parallel to get high voltage (or even do a combination of series and parallel to get whatever voltage you want).

 

[russ_watters]

I think we are talking about two different things.

And I am really not interested in derailing the thread with a debate about nuclear power.

Coal plants also operate on capacity factors of about 90%, so whether we talk about nuclear or not, you need to deal with the fact that replacing 1 MW of coal power capacity requires on the order of 8 MW of solar power. It's not a nuclear issue, it is a solar vs everything else (except wind...) issue.

 

[Skyhunter]

Like I said, we are talking about two different things.

I was referring to the panels conversion efficiency. CF would vary with location.

And it is interesting how you keep moving the goal post Russ. You used the same argument, different goal the last time I mentioned Nanosolar you used it to challenge the efficiency claim.

If everyone followed your advice there would be no progress because only the tried and true (according to personal judgement) would be acceptable.

I know this is hyperbolic... but you make such absolute statements I feel it necessary to use a little hyperbole.

I am not against using nuclear, and do not wish to divulge into an argument against it, but let's review a few facts. The capital costs of a nuclear plant are prohibitively expensive, $2.50/W to $5.00/W per so you are not being candid about the affordability. I don't know the exact cost of the utility panels, but the companies stated goal was to deliver a PV power plant for less than $1.00W.

I don't know if they met their goal, but the worlds leading producers and suppliers of electricity have bought up all there commercial production for the foreseeable future.

 

[Skyhunter]

And this is something that really irritates me about a good fraction of the people in the "alternate energy" crowd. Ignorance of the technology helps drive the fantasy. Skyhunter, high voltage or not, a solar panel makes DC power, period. It requires an inverter to integrate it with the grid.

In addition, being "high voltage" is an irrelevancy because you can always just wire solar panels in series instead of parallel to get high voltage (or even do a combination of series and parallel to get whatever voltage you want).

OK, I should have said higher current, not voltage. The higher voltage is however important for the higher current capacity and an overall benefit when designing a system.

Since the panels carry the current you don't need to wire the panels together to get the voltage you want. This amounts to a 75% reduction in cabling costs for both material and labor during installation.

And I should have said simpler to connect to the grid at municipal voltages. Of course one would need an inverter calibrated to the local grid.

I'll try and be more specific in the future to avoid irritating the mentors.

 

[mheslep]

Some very big energy players are invested in Nanosolar.

AES and EDF are some of the biggest in the world.

A 2MW plant requires ~10 acres,

In the US southwest for 15% panels it's more like 6MW over 10 acres, but only for ~five hours a day. Recall however that the OP asked about 50% renewables. Where then do we go for baseload power, i.e., something that works when the sun doesn't shine, and still get 50%? Without a storage mechanism that doesn't exist yet, 50% from solar is not possible.

 

[mheslep]

Commenting just on the nuclear vs solar cost:

...
The capital costs of a nuclear plant are prohibitively expensive, $2.50/W to $5.00/W per so you are not being candid about the affordability.

In the US, quotes for pending plants are more like $6/W. Shouldn't be, but apparently is. Even so ...

I don't know the exact cost of the utility panels, but the companies stated goal was to deliver a PV power plant for less than $1.00W...

If that becomes available, it is a cost per peak power figure, unlike the cost of nuclear which puts out rated power >90% of the time, the point of Russ's capacity factor post above. To replace ( or displace) an equivalent nuclear plant with solar PV compare all the costs:
1. To produce the same amount of energy in a day, multiply the PV figure by 6X in the southwest US, 8-10x in cloudier climates.
2. For the lower efficiency PV's like thin film, one needs a lot of land and a lot of installation. Maybe rooftops are free, or at least sunk costs. Certainly installation is not free. That $5/W for nuclear certainly includes 'installation'.
3. If its in the desert/ middle-of-nowhere add transmission costs, over and above nuclear transmission.
4. The overall cost has to include the 'other' energy source for nights/clouds, whatever it is. Maybe gas turbine electric.

Edit: the above reasoning changes if the if power is only needed for peak demand, like middle of the day air conditioning, and nothing more. However the OP wasn't looking for niche power, but 50% of the full time load.

 

[Skyhunter]

However the OP wasn't looking for niche power, but 50% of the full time load.

I think the OP was looking for 50% of energy coming from renewable energy. Since peak demand in during the hours when the Sun shines, solar can help fill that demand. With a smart grid, and using the batteries from electric vehicles, solar can be a significant contributor. Nuclear, especially fourth generation nuclear is a viable option, but not a magic bullet.

Solar at $1.00 a watt is economical enough to return a nice profit without subsidies. It can also be deployed in months instead of years, meaning that return on capital investment is much faster. A nuclear plant can take a decade or more to construct, tying up the investment capital during this period.

In the end, economics will determine what the makeup of our energy supply looks like. Solar power is fast becoming competitive with coal. Once these new panels hit the consumer market, look to see them on homes everywhere in the next decade.

 

[mheslep]

I think the OP was looking for 50% of energy coming from renewable energy.

Yes

Since peak demand in during the hours when the Sun shines, solar can help fill that demand.

Yes, help.

With a smart grid, and using the batteries from electric vehicles, solar can be a significant contributor.

Yes though I don't know what significant means here. I very much doubt 50% in the time frame of the OP.

Solar at $1.00 a watt is economical enough to return a nice profit without subsidies.

I see nothing here yet to support that assertion.

It can also be deployed in months instead of years, meaning that return on capital investment is much faster

I see this as one of the strongest points in favor of solar. Even transmission deployment disappears for rooftop installations.

A nuclear plant can take a decade or more to construct, tying up the investment capital during this period.

Yes, though that's a political consequence in the US, not something intrinsic to the technology.

In the end, economics will determine what the makeup of our energy supply looks like. Solar power is fast becoming competitive with coal.

Not true. In some scenarios, for peak power, solar PV is nearly competitive with peaking gas turbine plants, but not even close to coal without carbon taxes.

 

[mheslep]

Levelized cost of energy (not power) for multiple sources, before subsidies.

From http://www.newenergymatters.com/UserFiles/File/Presentations/NEF_2009-11-23_Guardian_Cleantech.pdf"
PV thin film 3-4X coal.

 

[edpell]

Levelized cost of energy (not power) for multiple sources, before subsidies.

From http://www.newenergymatters.com/UserFiles/File/Presentations/NEF_2009-11-23_Guardian_Cleantech.pdf"
PV thin film 3-4X coal.

Thank you for the reference. It is useful information.

Even at 4X I would think countries without coal deposits would be building.

 

[russ_watters]

Like I said, we are talking about two different things.

I was referring to the panels conversion efficiency. CF would vary with location.

Frankly, Skyhunter, we're talking about different things because you are talking about things that are irrelevant to the OP and/or factally wrong.

And it is interesting how you keep moving the goal post Russ. You used the same argument, different goal the last time I mentioned Nanosolar you used it to challenge the efficiency claim.

How exactly do you think I'm moving the goal posts? Where were they before and what are they now? Heck, I'm using your numbers in my calculations about the output prospects!

If everyone followed your advice there would be no progress because only the tried and true (according to personal judgement) would be acceptable.

You are misunderstanding/misrepresenting my position. In fact, I believe entrepreneurship is one of the primary components of US society that makes us great and I wish Nanosolar nothing but success.

But that doesn't have anything at all to do with the question the OP asked. The OP asked what could replace half of our energy with renewables in 20 years. And quite frankly, it almost doesn't even matter how good Nanosolar is - they (and related technologies/companies) almost certainly couldn't provide what the OP is asking for, even if the panels themselves were free!

I know this is hyperbolic... but you make such absolute statements I feel it necessary to use a little hyperbole.

I make absolute statements because from a technical and economic standpoint, the answer to this question is relatively simple. But at least you correctly judged your own statements to be hyperbole...

I am not against using nuclear, and do not wish to divulge into an argument against it, but let's review a few facts.

Ok...

The capital costs of a nuclear plant are prohibitively expensive, $2.50/W to $5.00/W per so you are not being candid about the affordability.

While your numbers look accurate, the idea that that is "prohibitively expensive" most certainly is not a fact. Those numbers are quite reasonable and in-line with what other forms of power cost. More importantly, those costs are artificially inflated due to political pressure. As a result, as the political climate warms to nuclear power, the per watt cost is likely to drop. Significantly. And in any case, the OP's question presupposes the existence of the political will to get the technically/economically most appropriate solution implimented.

Put another way, if the the American public said in unison, tomorrow, "lets do it!" (and meant it) to trying to replace 1/3 or so of our energy generation with solar (assuming we don't eliminate the existing hydro and wind fractions...), the project would almost certainly fail to reach that goal. If, on the other hand, they siad "lets do it!" (and meant it) to doing it with nuclear, the project would almost certainly succeed and cost several times less than the failed solar attempt.

I don't know the exact cost of the utility panels, but the companies stated goal was to deliver a PV power plant for less than $1.00W.

I had hoped that my previous analysis would head-off that inevitable misrepresentation. While it doesn't exactly rise to the level of a lie by the corporate literature, it does cause people to mistakenly believe that solar power is cost competitive.

As I already explained and mheslep explained again, $1/watt for solar is actually worse than $5/watt for nuclear. In addition, as mheslep said, those numbers are only valid if no attempt is made to mediate the power generation variation with storage. That limits the fraction of solar to perhaps 10% and requires 100% redundancy provided by (usually) natural gas.

I don't know if they met their goal, but the worlds leading producers and suppliers of electricity have bought up all there commercial production for the foreseeable future.

Who'se that, nanosolar? According to their website, they are only operating at 12 MW per month, only a small fraction of their capacity.

OK, I should have said higher current, not voltage. The higher voltage is however important for the higher current capacity and an overall benefit when designing a system.

Actually, the white paper I see says both higher voltage and current. But I think you still misunderstand what that actually does for you and why you can't just plug these into the power grid without an inverter. For starters, you should read up on what "ac power" is:
http://en.wikipedia.org/wiki/AC_power

In short, though, the voltage you get from your electrical socket is continuously varying sinusoidally from +170 to -170 volts, 60x per second. The voltage of a solar power does not vary sinusoidally and must be converted from DC to AC.

 

[Ygggdrasil]

Regarding the use of solar and wind to provide baseload power, the situation is not as bad as one might think. Sure, individual wind and solar plants will not be operational all the time (the average capacity factor for US wind projects in 2004-2008 averaged 35-37%[1]), but two factors mitigate the intermittentcy issues.

First, while a single individual wind/solar plant may experience wide variations in power output due to weather, the issue is not whether a single plant can supply baseload power but whether the collection of plants servicing an area can provide baseload power (the same applies to conventional fossil fuel and nuclear plants, while individual plants may experience breakdowns, baseload power is not interrupted because the other plants pick up the slack). Therefore, thinking in terms of an ensemble of renewable electricity sources, it is important to note that weather has different effects on different renewables (e.g. storms are obviously bad for solar but good for wind). Furthermore, weather will differ at different locations. Indeed, across an area of a few hundred miles, the correlations between windpower at different locations are low enough to trust that not all locations will experience below average wind. One study suggests that properly connecting at least ten windfarms can generate stable baseload power (without resorting to any sort of electricity storage involved, mind you) (2). Indeed, many studies in the US and abroad have shown that it is possible to generate a significant proportion of energy from wind without spending significant amounts of money on "firming" (i.e. providing redundant backup sources of energy to maintain baseload power should the output of the wind farms fail to produce enough energy). For example, with windpower providing 31% of total generation, the cost of firming the wind power adds only $0.005 per KWh to the cost (1).

The second factor mitigating issues with intermittency is that, because the variability in power output comes mainly from weather, the variability is predictable (weather forecasts are decent on the time scale of days and very good on the time scale of hours) and can be more easily accounted for and dealt with. Furthermore, the idea of distributing power generation over a greater number of smaller plants (i.e. the concept of micropower generation) means that more energy can be produced closer to the consumer which can help reduce the effects of grid failures (by far the biggest source of reliability issues) and can even improve efficiency since the electricity would not have to travel as far (it is estimated that electricity from new windfarms would travel about the same distance to consumers as from nuclear and fossil fuel plants. Solar, especially on rooftops in urban areas would do significantly better).

So, is it possible to use wind and solar to meet the 50% renewable goal set out in the opening post? It's conceivable (although I would agree that not within the 20 year timeframe). Already, various regions of Germany, Spain and Denmark get 30-40% of their annual electricity from wind without reliability problems (3). In fact, the entirety of Denmark is 20% windpowered today. While these locations represent the low hanging fruit, wind alone can clearly account for a large chunk of that 50% renewables goal.

On the issue of cost, the source that I've seen cites bottlenecks in nuclear reactor component supplies (some components have only one or two suppliers in the world) and the lack of people with the proper engineering skills as the main reasons for the high costs of building nuclear reactors, not political pressure (3). This fact is concerning because it suggests that the nuclear industry would not be able to support a rapid deployment of new nuclear reactors should we decide to go down that path. Indeed, perhaps Finland's new Olkiluoto-3 reactor -- 3 years behind schedule and 77% over budget after 3.5 years of construction (3) -- could be a sign of things to come if we decide to undertake a large scale program to increase our nuclear energy capacity. At the very least, one would take from this that in order to aggressively pursue nuclear energy in the future, we must first rebuild the nuclear industry (so the 20 year goal likely is not possible with nuclear).

Wind, on the other hand, is already competitive with conventional technologies although solar is not there yet. However, photovoltaic cells, like other semiconductor technologies, would be expected to progress following Moore's law, with costs dropping exponentially as the technologies mature. Furthermore, the concept of micropower (i.e. a large number of small energy production facilities) is amenable to the mass production of wind turbines and photovoltaics which could greatly lower their cost in the future. Given that we would need to rebuild the nuclear industry to pursue nuclear power, would it not be more sensible to instead focus on building a new, more promising solar industry? Most of the material was pulled from various article by Amory Lovins of the Rocky Mountain Institute, an independent, non-partisan, energy policy think-tank (main citation below). Lovins in a strong proponent of energy efficiency and renewable micropower generation and is a strong critic of nuclear power (so you can judge his biases). I would disagree with him that nuclear has no role in the future (there are likely locations where other technologies would not be suitable), but otherwise agree with his assessments that there are much more promising ways forward than nuclear for the majority of locations in the world. I would also agree with his points (not discussed here) that because new energy sources are relatively far in the future, improving energy efficiency is the best short term solution to our energy problems.

(1)M Bolinger & R. Wiser (2009), 2008 Wind Technologies Market Report. Lawrence Berkeley National Laboratories. http://eetd.lbl.gov/ea/ems/re-pubs.html

(2)Archer CL, Jacobson MZ. (2007). Supplying Baseload Power and Reducing Transmission Requirements by Interconnecting Wind Farms. J. Appl. Meteorol. & Climatol. 46(11): 1701-1717. http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175/2007JAMC1538.1

(3)Lovins AB (2009). Four Nuclear Myths. Rocky Mountain Institute. http://www.rmi.org/rmi/Library

 

[Al68]

And I am really not interested in derailing the thread with a debate about nuclear power.

Huh? How is the only reasonable direct answer so far to the OP derailing the thread.

Every other answer doesn't really answer the OP's question because it is either completely impractical or at least not feasible within 20 years. Nuclear power is very feasible to supply 100%+ of electrical power demand within 20 years, very green compared to the realistic alternatives, and most importantly is actually capable of delivering now. And it can be used to provide the power to extract hydrogen from seawater to power super-green vehicles in the future.

For all practical purposes, we are sitting on an unlimited supply of fuel for nuclear power plants, that will be around long after the memory of burning fossil fuels has faded. Unlike the alternatives, it's capable of keeping up with our growing need for power indefinitely, even without considering the likely huge advances in nuclear technology.

 

[mheslep]

Lovin's references have appeared in PF a few times. He's smart and interesting, so I find it useful to engage his ideas, but he also is a salesman and has a strong anti-nuclear stance. With that in mind ...

Regarding the use of solar and wind to provide baseload power, the situation is not as bad as one might think. Sure, individual wind and solar plants will not be operational all the time (the average capacity factor for US wind projects in 2004-2008 averaged 35-37%[1]), but two factors mitigate the intermittentcy issues.

First, while a single individual wind/solar plant may experience wide variations in power output due to weather, the issue is not whether a single plant can supply baseload power but whether the collection of plants servicing an area can provide baseload power (the same applies to conventional fossil fuel and nuclear plants, while individual plants may experience breakdowns, baseload power is not interrupted because the other plants pick up the slack). Therefore, thinking in terms of an ensemble of renewable electricity sources, it is important to note that weather has different effects on different renewables (e.g. storms are obviously bad for solar but good for wind). Furthermore, weather will differ at different locations. Indeed, across an area of a few hundred miles, the correlations between windpower at different locations are low enough to trust that not all locations will experience below average wind. One study suggests that properly connecting at least ten windfarms can generate stable baseload power (without resorting to any sort of electricity storage involved, mind you) (2). Indeed, many studies in the US and abroad have shown that it is possible to generate a significant proportion of energy from wind without spending significant amounts of money on "firming" (i.e. providing redundant backup sources of energy to maintain baseload power should the output of the wind farms fail to produce enough energy). For example, with windpower providing 31% of total generation, the cost of firming the wind power adds only $0.005 per KWh to the cost (1).

The second factor mitigating issues with intermittency is that, because the variability in power output comes mainly from weather, the variability is predictable (weather forecasts are decent on the time scale of days and very good on the time scale of hours) and can be more easily accounted for and dealt with.

I see heading towards 40% with improving technology for an annual average. However, in many parts of the US wind capacity swings http://www.uwig.org/opimpactspaper.pdf" down to ~15% (in the summer) over large areas, a fact not captured in those annual averages.

...Minnesota. Annual capacity factor of the wind plant is about 30%, with a seasonal high value of 40% for spring and a low value of 15% for summer.

Given this reality, I think wind is a very good match for the right kind of customer, like http://online.wsj.com/article/SB124623140359766167.html", who installed their own wind farm and can choose to run at max capacity when the wind is good and slow walk when its not. That doesn't work for the average home owner.

Furthermore, the idea of distributing power generation over a greater number of smaller plants (i.e. the concept of micropower generation) means that more energy can be produced closer to the consumer

Yes, though micro means moving away from the 50% goal. Wind and solar have their geographic sweet spots, their economics are three to five times better in some areas than others. That means large, centralized solar in the southwest and wind in the midwest, with transmission to other areas.

So, is it possible to use wind and solar to meet the 50% renewable goal set out in the opening post? It's conceivable (although I would agree that not within the 20 year timeframe). Already, various regions of Germany, Spain and Denmark get 30-40% of their annual electricity from wind without reliability problems (3).

Small regions, which are highly interconnected with traditional power sources to handle low wind/solar output.

In fact, the entirety of Denmark is 20% windpowered today. While these locations represent the low hanging fruit, wind alone can clearly account for a large chunk of that 50% renewables goal.

Yes 20%, but I see the evidence as saying it will be difficult to exceed that. This, in a country with only ~12GWe of capacity (1% of the US)

[...]Indeed, perhaps Finland's new Olkiluoto-3 reactor -- 3 years behind schedule and 77% over budget after 3.5 years of construction (3) -- could be a sign of things to come if we decide to undertake a large scale program to increase our nuclear energy capacity.

Even with the overrun the final cost of Olkiluoto-3 is likely to behttps://www.physicsforums.com/showpost.php?p=1951197&postcount=237" installed.

 

[Skyhunter]

Frankly, Skyhunter, we're talking about different things because you are talking about things that are irrelevant to the OP and/or factally wrong.

I misunderstood Argentum's question. When he asked for the panel's CF, I thought he wanted to know the panel efficiency, since capacity factor is not a panel rating.

Now what is irrelevant or factually wrong about that?

How exactly do you think I'm moving the goal posts? Where were they before and what are they now? Heck, I'm using your numbers in my calculations about the output prospects!

Last time you challenged the cost/efficiency claims with the same argument you are using now. The efficiency claims were 14% and even though the Germans had confirmed the efficiency you dismissed it. (actual active area efficiency is >16%) Because the only working plants are privately owned there is no available data yet for the actual output from the solar power plants using the new panels. Once again you are using the same "unproven argument with a different goal.

And if you are using my numbers, for your capacity factor calculation you are using the wrong numbers, because I never provided any.

You are misunderstanding/misrepresenting my position. In fact, I believe entrepreneurship is one of the primary components of US society that makes us great and I wish Nanosolar nothing but success.

Am I?

The only thing that could possibly meet your criteria at a resonable price is nuclear power.

Because I'm assuming the OP isn't asking about fantasy or science fiction. If we want to discuss what can be done, nuclear power is the only possible solution that can do what the OP asks at a reasonable price (and that's generous: it may actually just plain be impossible any other way).

All of those are hypotheticals. They have not been proven to be viable yet. Nuclear has. Why bet our future on maybes when we have a can available?

I absolutely agree that green jobs are a good idea. So we should start immediately on hundreds of new nuclear plants. That would create hundreds of thousands of new green jobs.

That's nice but until it actually happens - until someone builds a commercial scale plant using their technology - it is still hypothetical.

Seems to me you are saying put everything into nuclear. That is you opinion and you are entitled to it. My opinion is different. And I am entitled to it.

But that doesn't have anything at all to do with the question the OP asked. The OP asked what could replace half of our energy with renewables in 20 years. And quite frankly, it almost doesn't even matter how good Nanosolar is - they (and related technologies/companies) almost certainly couldn't provide what the OP is asking for, even if the panels themselves were free!

So in your opinion nuclear is the only possible solution. My opinion is that we can use a multi-faceted approach. Since the OP specifically mentions solar power, my discussing it is not off topic.

I make absolute statements because from a technical and economic standpoint, the answer to this question is relatively simple.

The question as you understand it perhaps. Regardless, it is still just your opinion.

While your numbers look accurate, the idea that that is "prohibitively expensive" most certainly is not a fact. Those numbers are quite reasonable and in-line with what other forms of power cost. More importantly, those costs are artificially inflated due to political pressure. As a result, as the political climate warms to nuclear power, the per watt cost is likely to drop. Significantly. And in any case, the OP's question presupposes the existence of the political will to get the technically/economically most appropriate solution implimented.

That is a hypothetical.

Put another way, if the the American public said in unison, tomorrow, "lets do it!" (and meant it) to trying to replace 1/3 or so of our energy generation with solar (assuming we don't eliminate the existing hydro and wind fractions...), the project would almost certainly fail to reach that goal. If, on the other hand, they siad "lets do it!" (and meant it) to doing it with nuclear, the project would almost certainly succeed and cost several times less than the failed solar attempt. I had hoped that my previous analysis would head-off that inevitable misrepresentation. While it doesn't exactly rise to the level of a lie by the corporate literature, it does cause people to mistakenly believe that solar power is cost competitive.

The OP was not asking for a single magic bullet. There is no reason I can see not to pursue both strategies.

As I already explained and mheslep explained again, $1/watt for solar is actually worse than $5/watt for nuclear. In addition, as mheslep said, those numbers are only valid if no attempt is made to mediate the power generation variation with storage. That limits the fraction of solar to perhaps 10% and requires 100% redundancy provided by (usually) natural gas.

The CF for solar in Arizona is about 20%. Average in the US is around 12%-17% Thermal energy storage can be used to extend baseload coverage. But then, I am not arguing to replace 50% of our energy production with solar. I am simply trying to discuss one facet of the picture.

Who'se that, nanosolar? According to their website, they are only operating at 12 MW per month, only a small fraction of their capacity.

Which factory? They have one in Germany, and one in San Jose which they are expanding.

Actually, the white paper I see says both higher voltage and current. But I think you still misunderstand what that actually does for you and why you can't just plug these into the power grid without an inverter. For starters, you should read up on what "ac power" is:
http://en.wikipedia.org/wiki/AC_power

In short, though, the voltage you get from your electrical socket is continuously varying sinusoidally from +170 to -170 volts, 60x per second. The voltage of a solar power does not vary sinusoidally and must be converted from DC to AC.

I am not misunderstanding what voltage and current do. You misunderstood me, and seem to be ignoring my explanation.

I never said you could plug a DC panel into an AC socket.

The advantage of these panels, and their ability to carry higher currents at higher voltage, is reduced material and labor costs. Because these panels carry the current themselves, there is no need for extra cabling to the inverter. Because each series is operating at 50% higher voltage, fewer series are needed to step up to distribution voltage.

 

[Skyhunter]

http://news.stanford.edu/news/2009/october19/jacobson-energy-study-102009.html" published in Energy and Environmental Sciences whose authors argue we can get 100% from renewables in 20 years.

 

[SystemTheory]

My regrets to anyone on the thread who considers my prior posts to have been spreading misinformation. Here is a link to a 79 page pdf from the International Atomic Energy Agency discussing the Use of Reprocessed Uranium: Challenges and Options:

http://www-pub.iaea.org/MTCD/publications/PubDetails.asp?pubId=8010

And I intend to read every page later tonight. I realize it is theoretically possible now and in the future to keep hazardous industrial materials in a continuous loop. This is not the same as saying "nuclear waste does not exist" because when it fails to be contained it is waste that carries the hazards of ionizing radiation or toxic impact due to dispersion and ingestion. If anyone wants a list of radiation accidents search the term and plenty of evidence will pop right up.

 

[Skyhunter]

My regrets to anyone on the thread who considers my prior posts to have been spreading misinformation. Here is a link to a 79 page pdf from the International Atomic Energy Agency discussing the Use of Reprocessed Uranium: Challenges and Options:

http://www-pub.iaea.org/MTCD/publications/PubDetails.asp?pubId=8010

And I intend to read every page later tonight. I realize it is theoretically possible now and in the future to keep hazardous industrial materials in a continuous loop. This is not the same as saying "nuclear waste does not exist" because when it fails to be contained it is waste that carries the hazards of ionizing radiation or toxic impact due to dispersion and ingestion. If anyone wants a list of radiation accidents search the term and plenty of evidence will pop right up.

Thanks.

This is exactly the type of nuclear technology I hope we pursue.

 

[zomgwtf]

On the topic of radioactive waste I tend to think more of the uniforms that are worn and things of that nature. They still contain harmful levels of radiation and so they must be disposed of.

Nuclear fuel rods I'm pretty sure can be MOSTLY re-used I'm pretty sure that the United States doesn't do this but that doesn't imply 'it can't/shouldn't be done'.

 

[Argentum Vulpes]

My regrets to anyone on the thread who considers my prior posts to have been spreading misinformation. Here is a link to a 79 page pdf from the International Atomic Energy Agency discussing the Use of Reprocessed Uranium: Challenges and Options:

http://www-pub.iaea.org/MTCD/publications/PubDetails.asp?pubId=8010

And I intend to read every page later tonight. I realize it is theoretically possible now and in the future to keep hazardous industrial materials in a continuous loop. This is not the same as saying "nuclear waste does not exist" because when it fails to be contained it is waste that carries the hazards of ionizing radiation or toxic impact due to dispersion and ingestion. If anyone wants a list of radiation accidents search the term and plenty of evidence will pop right up.

I did look up "radiation accidents" and all I could find that would seriously concern me (living here in the USA) was the radioactive boy scout, the Therac-25, and several cases of a CT tec screwing up badly.

Every other accident couldn't happen here. Medical equipment being just dumped, RTGs being lost, scrap metal being brought back into the production stream when it wasn't ready, or reactors with an operator bent on breaking it.

If you could point out an accident where a NRC certified and regulated power plant caused major harm to the public I'd like to know about it. Heck if you could find a case where used nuclear fuel here in the USA caused major harm to the public I'd also like to know about it.

Just remember we live on a planet surrounded by radioactivity from the soil, the food we eat, the water we drink, and cosmic rays. The natural background radiation count is 300 mrem with it being higher in most places. The USA congress building is so hot it would never be able to licensed as a nuclear power plant.

 

[DrClapeyron]

http://news.stanford.edu/news/2009/october19/jacobson-energy-study-102009.html" published in Energy and Environmental Sciences whose authors argue we can get 100% from renewables in 20 years.

I read this from the conclusion in the report:

Ideally, good locations of energy resources would be sited in advance and developed simultaneously with an interconnected transmission system.

If all carbon resources droped dead tomorrow, nuclear would be the only fall back. Niche ideas in the oil glut age would be cast aside without a moment's hesitation.

 

[Skyhunter]

If all carbon resources droped dead tomorrow, nuclear would be the only fall back. Niche ideas in the oil glut age would be cast aside without a moment's hesitation.

A highly improbable scenario.

Why even try and predict the outcome of such an unlikely event.

 

[SystemTheory]

The advantage of these panels, and their ability to carry higher currents at higher voltage, is reduced material and labor costs. Because these panels carry the current themselves, there is no need for extra cabling to the inverter. Because each series is operating at 50% higher voltage, fewer series are needed to step up to distribution voltage.

The other advantage is power produced at high voltage draws less current and reduces the proportion of waste heat (oh no, I said "waste"!). Thus the efficiency should be higher and the series/parallel configuration of panels is more efficient in larger series stack. This is also true for DC batteries in an off-grid system, rechargable power tools, etc.

Phrases such as "nuclear waste does not exist" are not going to win any converts from the public. It is good for starting controverseys, selling books, and newspapers. I note that even the International Atomic Energy Agency publishes a number of Safety titles using the phrase "radioactive waste."

http://www-pub.iaea.org/mtcd/publications/ResultsPageSSS.asp

On the issue of it "can't happen here" my link to the Hanford nuclear waste site was deleted. According to the GAO report I posted, the radioactive material is sitting around 20 years after the "cleanup" and reprocessing was supposed to begin. I don't think one can blame politics as an impediment in this case, since the Superfund budget is being paid from the Fed/taxpayer ability to create unlimited funds, and the Government itself is authorized to do the work. This is the political thread so if anyone wants to advocate nuclear power using facts or rhetoric, go ahead. I'm a big boy now who can sift facts versus BS all by myself. I assume everyone else here could do the same without crying foul, but then, recent personal history has proven this theory wrong.

 

[SystemTheory]

On the issue of it "can't happen here" my link to the Hanford nuclear waste site was deleted. According to the GAO report I posted, the radioactive material is sitting around 20 years after the "cleanup" and reprocessing was supposed to begin. I don't think one can blame politics as an impediment in this case, since the Superfund budget is being paid from the Fed/taxpayer ability to create unlimited funds, and the Government itself is authorized to do the work.

I voluntarily relax this statement about politics not being an issue based on reading this report about the law suit between the State and DOE over the Hanford cleanup:

http://crosscut.com/2009/02/05/hanford/18832/

although it appears (from what I can fathom) that the politics are internal to the DOE and Fed agencies, and/or the technical and financial challenges are greater than originally anticipated. I am not sure the public distinguishes between DOE, the military, and the nuclear industry because the historical nexus of connections called "the military industrial complex (MIC). I don't recall a reference, but I recall President Eisenhower warned about the concentrated power of the MIC.

 

[Ygggdrasil]

I see heading towards 40% with improving technology for an annual average. However, in many parts of the US wind capacity swings seasonally down to ~15% (in the summer) over large areas, a fact not captured in those annual averages.

A very good point especially because summer is a time of peak electricity demand in many places of the world that require air conditioning. Hopefully solar technologies (once they become competitive enough to enter the marketplace) could replace some of the lost capacity as solar would be expected to have above average capacity during the summer.

Yes, though micro means moving away from the 50% goal. Wind and solar have their geographic sweet spots, their economics are three to five times better in some areas than others. That means large, centralized solar in the southwest and wind in the midwest, with transmission to other areas.

Micropower generation (i.e. distributed power generation) does not necessarily mean less power generated. A good analogy here would be to distributed computing (splitting up large computational challenges into smaller pieces that can be processed in parallel on small, cheap, mass produced computers). Distributed computing is able to use cheap, simple technology to perform tasks that normally would require a big, expensive supercomputer. In a similar way, large numbers of relatively cheap, mass-produced wind and/or solar installations spread out over a wide area could generate as much power as a larger installation and do so more robustly (since a more distributed power generation network would be less susceptible to grid failures or unfavorable weather in a particular location).

Yes 20%, but I see the evidence as saying it will be difficult to exceed that. This, in a country with only ~12GWe of capacity (1% of the US)

Two countries would beg to differ: the UK and Denmark. Various studies looking at the impact of wind intermittency in the context of British weather patterns have estimated that the UK could generate 30-40% of its electricity from windpower with only modest increases in its firming capacity (1). These increases would add only ~6% to the cost of the electricity.

Denmark has even more ambitious goals and plans to generate 50% of their electricity from wind by 2025. In Denmark, however, intermittency is a significant issue but can be dealt with by storing wind energy. Luckily, Denmark is near Norway, a country with many hydroelectric plants. Therefore, Denmark can easily store its excess wind energy by using the excess electricity to pump water up to reservoirs in the mountains where it can be stored indefinitely and harvested during periods of low wind. Pumped hydroelectric storage is one of the few mature, effective energy storage methods available (with 70-85% storage efficiency[2]) that is already in use across the globe.

Are the UK and Denmark special cases? Of course. Both countries have plentiful offshore wind resources, the UK is fortunate to have fairly constant winds, and Denmark is lucky to neighbor a country with plentiful hydroelectric resources. However, I would contend that every country is a special case. Each individual region will have a different climate, different resources and different challenges that it must consider when planning its future energy economy. A one-size-fits-all solution does not exist. To claim (as others in the thread have said, though not you) that nuclear power is the only option is clearly false. There will be regions where nuclear is the best option but there will be other regions where options like wind are the better choice. The US, for example, has lost of coal available very cheaply. Although there are serious concerns about whether carbon capture and sequestration can be done cheaply and safely, maybe this will end up being the best solution for much of the US (although it will definitely fall out of the 20 years range).

Now, the opening post asked whether it is possible for the US (or any other country) to generate more than 50% of its energy from renewable sources. Denmark is on track to do exactly that and it is possible that other countries will be able to follow as new technologies come into the marketplace.

(1) Studies summarized here: http://www.claverton-energy.com/wind-energy-variability-new-reports.html
(2) Lindley D. (2010) Smart grids: The energy storage problem. Nature 263: 18-20. doi:10.1038/463018a

 

[mheslep]

http://news.stanford.edu/news/2009/october19/jacobson-energy-study-102009.html" published in Energy and Environmental Sciences whose authors argue we can get 100% from renewables in 20 years.

The actual study in your second link in (E&E) does not argue that, or make any reference to a 20 year plan. It compares and ranks various energy sources. Perhaps that claim, as made in the Stanford news release link, is detailed in the mentioned Scientific American article by the same authors.

 

[mheslep]

..Micropower generation (i.e. distributed power generation) does not necessarily mean less power generated.

Yes it does, if micro means close to residential scale. For the case of renewables the resources are not evenly distributed, so concentrating installations in areas of greater resource necessarily means more energy generation than an even distribution across every roof top in the country, North to South. In the US this means the southwest for solar, and the midwest corridor (or offshore) for wind. This doesn't mean that a lot of micro power can't be done, it is, and more will. It just won't be limited to the scale of backyard wind turbines, nor will solar consist of only 10kw panel sets on every US roof.

Two countries would beg to differ: the UK and Denmark.

Not the countries; the studies differ, supposedly.

Various studies looking at the impact of wind intermittency in the context of British weather patterns have estimated that the UK could generate 30-40% of its electricity from windpower with only modest increases in its firming capacity (1). These increases would add only ~6% to the cost of the electricity.

Can you please actually cite the relevant parts in anyone study claiming up to 40%? Lots of things are possible,but I am referring to the experience reported now, like the Texas outage reported in the Nature link:

In February 2008, during a sudden cold snap, the normally relentless winds of west Texas fell silent and the thousands of wind turbines that dot that part of the state slowed to a halt. Local utility operators, unable to make up the shortfall with power from elsewhere in the grid, were forced to cut service to some users for up to an hour and a half before the winds picked up again

Texas already has more than double the wind turbine capacity of Denmark.

Denmark has even more ambitious goals and plans to generate 50% of their electricity from wind by 2025. In Denmark, however, intermittency is a significant issue but can be dealt with by storing wind energy. Luckily, Denmark is near Norway, a country with many hydroelectric plants. Therefore, Denmark can easily store its excess wind energy by using the excess electricity to pump water up to reservoirs in the mountains where it can be stored indefinitely and harvested during periods of low wind. Pumped hydroelectric storage is one of the few mature, effective energy storage methods available (with 70-85% storage efficiency[2]) that is already in use across the globe.

http://blogs.wsj.com/environmentalcapital/2008/03/11/thar-she-blows-dongs-wind-woes/?mod=WSJBlog" says 30% by 2025:

When a hard wind blows across Denmark’s green plains, Anders Eldrup, chief executive of the power company DONG, shudders. Not because of the bone-chilling cold, but because his company’s power grid is under enormous strain.

On windy days, some 30-50% of the electricity flowing into the grid comes from wind turbines that dot the countryside. At less windy times, turbines spin more slowly and send much less electricity through the grid. The grid infrastructure wasn’t designed for such fluctuations. What’s more, windy days bring in more electricity than DONG can profitably sell.

It’s a problem of success. A decade of Denmark’s generous subsidies to wind power producers has produced striking results: Some 16% of the country’s total electricity needs come from wind. Denmark’s government wants to be getting 30% of its electricity from renewable sources by 2025. “It’s an increasingly difficult challenge for us,” said Mr. Eldrup in an interview on the sidelines of an ongoing Carbon Market Insights conference taking place this week in Copenhagen.

Denmark already has high power connections to other countries, but in wind lulls Denmark makes up much of the slack using German coal and Swedish nuclear. Also I'm familiar with pumped storage, however, I'm unaware of significant pumped storage connected to Denmark's grid via Norway or Sweden, versus normal hydro. Generally grids with abundant hydro store energy by simply slowing or stopping the dam flow and allowing the water to collect behind the dam, but not pumping it up as the facilities were not designed that way originally.

Now, the opening post asked whether it is possible for the US (or any other country) to generate more than 50% of its energy from renewable sources. Denmark is on track to do exactly that and it is possible that other countries will be able to follow as new technologies come into the marketplace.

No Denmark is not 'on track' for 50%. They have some studies and goals, with storage 'long term' plans possibly using batteries and fuel cells, none of which exist yet in any scale. Perhaps that can be done, and good luck to them, but its by no means proven.edit: Note Denmark also has the highest electricity rates in the world of reporting countries - 32 cents/kWh (2006).
http://www.eia.doe.gov/emeu/international/elecprih.html

 

[DrClapeyron]

A highly improbable scenario.

Why even try and predict the outcome of such an unlikely event.

It's the scenario posted by the OP: how to gain energy independence in 20 years. If the US found out that in 20 years oil and coal would run dry, I can sure as heck see the scenario being highly probable. There already is a large industrial nation with nuclear energy as a very high percent of its nation's energy output: France. Can't say the same for the niche ideas.

 

[SystemTheory]

This is a NASA article about the Net Primary Production:

http://earthobservatory.nasa.gov/Features/HANPP/hanpp.php

which is the solar powered energy that supports all human consumption and powers life on earth. Although the OP asks about energy independence in the short run, there is a flaw in the question, because humans live through energy interdepence in the food web.

Page 2 (html) of this paper estimates New York City is dependent on external sources of NPP by a factor of 30,000 percent above its own contribution to NPP. Thus, a politician in New York City who argues that Wall Street supports upstate New York via tax subsidies, is like a man standing on his head, because upstate New York supports Wall Street with the production of real goods and services, not the other way around! The problem with capitalist ideology and measuring everything in $ cost is that it introduces many distortions in one's long term reasoning process.

Personally I think a commitment to nuclear + H2 production might benefit the people in the short run, but it would still be a system based on a form of interdependence, which depends on who owns and controls the fuel sources. If we go to dependence on nuclear + H2 in a big way it could have implications for centuries to come, and these might preclude better long run alternatives.

The way nature captures NPP is to convert solar radiation to high energy electrons in the process we call photosynthesis. This is a clean distributed energy source existing today on land and in the Oceans providing clean renewable power all over the globe! In the long run the answer to the question is that energy independence is itself rhetoric, since liife is a process of interdependence, and the politics of which technologies and social systems one is becoming dependent upon in the long run should enter into a reasonable discussion. Also the lessons of history and the dismal legacy of the MIC in keeping secrets from the public cannot be simply swept away by rhetoric!

 

[mheslep]

This is a NASA article about the Net Primary Production:

http://earthobservatory.nasa.gov/Features/HANPP/hanpp.php

which is the solar powered energy that supports all human consumption

Maybe most, but far from all. NPP as defined there excludes, for example, all of wind, geothermal, nuclear, and solar PV or solar thermal collection would be alternatives to NPP - "the amount of plant material left over after respiration"

and powers life on earth. Although the OP asks about energy independence in the short run, ...

No, the https://www.physicsforums.com/showpost.php?p=2534829&postcount=1" asked about renewable energy providing up to 50% of total load. That and independence are not necessarily the same thing.