Tuesday, April 29, 2014

Let's Lobby!

In the energy discourse it is almost impossible to obtain "fair and balanced" information. It seems everybody out there is lobbying for something, consequently "their" energy is perfect, emits zero pollutants, and creates loads of jobs while the "other" energy is the devil. As easy as that. However, real life, as always, is not black or white, we really don't have out there a picture-perfect solution for a nonexistent binary world.

Can we begin to talk, listen and respect each other instead of just pointing fingers (and even hurling insults)?

Lobbyists are PAID to blindly defend a position and thus they should probably not even be invited to the conversation because as Upton Sinclair stated:

"It is difficult to get a man to understand something, when his salary depends upon his not understanding it."

On the other hand, the REST of us should employ very healthy doses of skepticism when listening to them. Let's label them as what they really are: paid advertisers.

So, let's stop flying and make a soft landing. Here are some basic things we all need to understand:

  • No energy is clean. Period. End of story. Elvis has left the (pick one): solar panel / wind turbine / nuclear reactor / dam. 
  • Thus, no energy is zero emissions (once you consider the lifetime emissions of the respective technology). 
  • The most we can say is that something is cleaner or lower carbon than something else. 
  • When discussing subsidies, let's not say x receives so many dollars and y receives only this other amount. Things have to be stated in subsidies per energy produced to have a reference point.
Now, let's briefly scan the main energy sources and focus only on their most important characteristics. Let's not be distracted with side issues (like if wind turbines kill more birds than skyscrapers or not). 

Fossil Fuels:
  • They are high carbon.
  • In particular coal, causes a substantial number of casualties during its extraction.
  • In addition to carbon, they liberate other important pollutants to the environment.
  • Not considering externalities, they are the cheapest energy sources we have on a global scale.
  • Our current infrastructure is built around them.
  • They are convenient, reliable, flexible, high density energy sources. 
  • Entire countries depend on the revenue they produce not to mention many millions of jobs all over the world.
  • Carbon Capture and Storage (CCS) has not been widely deployed. 
  • According to the EIA, IEA, they will continue to dominate the energy market for decades to come. 
Now, let's take a look at the low carbon energy sources.

Sun and Wind:
  • They are intermittent and unreliable and no amount of spin can change this. The low costs quoted for these technologies consider them piggy-backing on the conventional grid. If they were required to pay for the full effects of their intermittency / unreliability their costs would skyrocket.
  • As an individual component, they seem to be low carbon, but once the system is considered (RE + FF backup), the emissions go up enough to even question if they are truly low carbon solutions.
  • Storage or other means to compensate for the above have not been widely deployed.
  • It is reliable, dense, safe, scaleable and produces little (although dangerous) waste.
  • Is currently fighting an uphill battle against irrational fears planted by lobbyists (see above).
  • Globally, it currently holds the highest market penetration in the production of low carbon electricity.
  • It has served us well for many, many decades.
  • As a percentage of our total energy consumption, it probably has reached its peak. 
Conclusion: the move away from fossil fuels will be gradual, will take many decades and they will not be replaced by the perfect energy source (which doesn't exist). We need to make hard sensible decisions minimizing the effects of the "paid advertisers."

Feel free to add to the conversation on Twitter.

Thank you.

Labels: , , , , , , , ,

Friday, April 25, 2014

Solar Photo-voltaic: Let's Get Real

This exercise is a simplification in which we try to explain why solar photo-voltaic (PV) has difficulty in living up to its hype.

Let's consider an isolated country that consumes on average 40 GW of electricity.

To simplify things, let's consider they consume this amount of power 24 hours a day. In real life, consumption has peaks and valleys.

They plan to install enough solar PV to supply 100% of the electrical energy of the country at peak solar production.

Again, to simplify, let's consider a perfectly cloudless day during the spring or fall equinox. The output would look like this:

So, from midnight to 6 AM, another energy source would supply 100% of the electricity.
Then again, from 6 PM until midnight, another energy source would supply 100% of the electricity.
Then, from 6 AM until 6 PM solar would provide continually variable production and will reach 100% of this country's energy needs at local noon. In other words, at local noon, solar PV would be producing 40 GW of power. (8)

What would happen if this country decided to go above 100% solar at peak production (as an isolated country, they couldn't "dump" the excess production into another country. Also, we are not considering storage that could be an article in itself).

Then, they would have to curtail (disconnect) solar capacity at peak production hours. This is how the graph would look (100% peak vs. 125% peak comparison):

As we may see, there is not too much sense in taking the PV capacity above the peak requirements.

Now, how would the production of the "other" sources (usually fossil fuels) look to compensate for the variable nature of PV. Here we can see it:

In other words, from midnight to 6 am, and from 6 pm until midnight, the other source would supply 100% of the electricity. Then from 6 am to 6 pm it would have to continually adjust its output to compensate for the PV production. 

If the Earth were a perfectly cloudless planet, this sort of arrangement would allow PV to provide close to one third the energy requirements of a country. What would be the carbon intensity of such electricity? Here we calculate it:

According to the table referenced below, solar PV has a carbon intensity of 46 grams per kWh, and let's say the rest of the electricity is produced by natural gas (469 grams per kWh), thus the combined carbon intensity would be:

     46 x 0.33 + 469 x 0.67 = 329 grams per kWh.

However, in real life the Earth is not cloudless and thus the actual annual capacity factor of solar PV is closer to 15%. If we re-calculate with this more realistic number, we get:

     46 x 0.15 + 469 x 0.85 = 406 grams per kWh.

If a component of coal is used in the "other" energy then the emissions would rise even higher. 

Again, this article is a simplification, but the point is to explain in simple terms why solar PV is not living up to its hype.

Thank you.


1. In real life, clouds reduce the output of the solar panels.
2. Seasonality also greatly impacts power generation: winter days are shorter and possibly cloudier.
3. The "other" power plants need to be idled, modulated, shut down, restarted and this causes inefficiencies in the system and additional emissions.
4. From a purely operational point of view, "nothing would happen" if all solar capacity were disconnected.
5. Yes, a solar + fossil fuels system produces less emissions than a purely fossil fuel one, but at the cost of duplicated investment.
6. Yes, excess solar energy could be "dumped" into another country, but if that country also installed significant solar capacity, this wouldn't be an option anymore. 
7. The other option is storage but currently this (expensive) technology hasn't been widely deployed. Also, storage would add to the emissions per kWh (once life-cycle emissions are taken into consideration).
8. "Local noon" doesn't happen at the same time in all the country, so the curve would be a little bit flattened. 


Labels: , , , , ,

Thursday, April 24, 2014

Going Nuclear

This is a simplified exercise to visualize what would be required to convert 50% of the world's electricity to nuclear, the premier low carbon source.

According to the EIA (Energy Information Administration) latest report, the global generation of electricity in 2010 was 20.2 trillion kWh, and they project that by 2040 total global generation will reach 39.0 trillion kWh.

So, if we decide to generate 50% of our electrical energy with nuclear (at, say, an average 80% capacity factor), we would require this number of 1 GWe reactors:

     50% of 39.0 trillion kWh is 19.5.

Let's convert trillion kWh to GWh by multiplying it by one million:

     We now have 19,500,000 GWh.

A 1 GWe nuclear plant at 80% capacity factor (CF) produces, on an annual basis:

     1GWe x 0.80CF x 24 hrs x 365 days = 7,008 GWh.

Thus, we would need this number of reactors by 2040:

     19,500,000 / 7,008 = 2,783.

Simplifying thing a little, let's consider that half of the current nuclear plants will still be in operation by 2040. According to the EIA, nuclear supplied 2.6 trillion kWh in 2010. This would correspond to the equivalent of 371 1 GWe reactors at 80% CF. If half of these are in operation by 2040, we can subtract 186 from the number calculated above, thus we get:

     2,783 - 186 = 2,597 new nuclear reactors.

If we have 30 years to build them, it would require the commissioning of:

     2,597 / 30 = 87 nuclear reactors EVERY year for 30 CONSECUTIVE years.

And again, let's remember that the above effort would only yield 50% of our global electricity and around 25% of our total energy consumption by 2040.

At the end of the day we have to differentiate what is possible, from what is probable.

The probability of this nuclear build up taking place by 2040 is, in my humble opinion, less than zero.

Feel free to add to the conversation.

Thank you.

EIA electricity projections from their latest report:

1. By 2040, only ~50% of our energy consumption will be electricity.
2. There is no such thing as a global grid, so the real life implementation would be more complicated than pictured above.
3. Sure, many questions need to be answered, starting with determining if we even have the manufacturing capacity required to make such a ramp up.
4. Nuclear has a serious advantage over RE (sun and wind): it is baseload, reliable power.
5. Of the renewable power in 2040, fully 65% is estimated to be hydro.
6. Yes, there are reactors bigger and smaller than 1 GWe, we are considering all of them at 1 GWe to simplify.

Labels: , , , , , ,

Tuesday, April 22, 2014

Greenpeace Interview

This is a fictional interview with a retired executive director of Greenpeace taking place, say, two decades in the future.

GNWR: Thank you, Mr. GP for accepting to participate in this interview. We know that since your retirement you have not conceded any other interview, so we really appreciate your kindness with us.

Mr. GP: It is my pleasure.

GNWR: How do you evaluate the accomplishments of Greenpeace during your tenure.

Mr. GP: I think the balance is positive.

GNWR: Is there anything you would have done differently if you started again.

Mr. GP: Is this on the record?

GNWR: Yes, sir.

Mr. GP: Well... I... yes... let me be candid. We fought the wrong enemy.

GNWR: What do you mean by that?

Mr. GP: We fought nuclear energy too hard and now I know it is, aside from hydro which has limited capacity to grow, the premier low carbon energy source humanity has access to. So here we are, decades later, using more fossil fuels than ever and... sometimes I wonder if we were actually a barrier to real progress in climate action.

GNWR: Did you have this epiphany after leaving Greenpeace?

Mr. GP: Well... not exactly, but, you see, we are sort of a corporation and our revenue are the funds we receive from millions of persons around the world and, how can I say it... we needed a boogeyman.

GNWR: And nuclear was it?

Mr. GP: Not only nuclear, fossil fuels were in theory our main target, but nuclear has a capacity for generating irrational fears that fossil fuels cannot match, so we invested much more than our fair share in demonizing nuclear.

GNWR: And what was the final result.

Mr. GP: Well, we got our funding, alright, but as an environmental movement, we went nowhere and here we are decades later, the honeymoon with solar and wind gone, and nuclear, the only feasible, fully scaleable solution to reducing our civilization's carbon footprint is way behind where it could have been by now.

GNWR: Do you blame yourself for this?

Mr. GP: Only in part. Greenpeace was not the only environmental organization opposing nuclear. It was the fad of the moment and yes, GMOs were also unjustly attacked.

GNWR: Do you plan to mend your ways now?

Mr. GP: Not publicly. Greenpeace has now more pragmatic people leading it. This time, I think, they will really help move the environmental agenda forward.

GNWR: By supporting nuclear?

Mr. GP: Look, let's face it, even if we consider nuclear the devil we have to concede it is a low carbon devil. Besides, the new designs are safer than anything we had in the past and in all truth all things in life have an element of risk. The alternative would be to shut down civilization and go back to caves.  But that, of course, would also imply grave risks, so, there is no way out of nuclear, at least not now.

GNWR: We thank you for this extremely candid conversation you had with us.

Mr. GP: Thank you.  I actually feel better for having had this candid conversation.

Labels: , , , , , ,

Sunday, April 20, 2014

Living in the Material World

Let's make a comparison on the amount of "material" that is needed by two different electricity production sources.

First, let's start with nuclear. According to the MIT study referenced below, 200 tons of natural uranium (in other words, as it comes out of the mine) produce 1 GWe for a full year.

To convert this to GWh, we multiply 1GWe x 365 days x 24 hours = 8,760 GWh.

To scale this down to a more manageable amount we'll calculate the electricity production per ton of natural uranium:

     8,760 GWh / 200 = 43.8 GWh.

Now, let's estimate how much material is required to produce this same amount of electrical energy with solar photo-voltaic panels.

Searching in Amazon, I found 250 Watt solar panels that weight 19 kgs (sure, other models may weight less or more). We'll use these panels in our exercise, considering they have a useful life of 25 years. Also, we'll be optimistic and consider a capacity factor of 20% during the useful life of the panels.

One 250 W panel would then produce:

     250 W x 20% (capacity factor) x 24 hours x 365 days x 25 years = 10.95 MWh.

How many panels would be required to produce 43.8 GWh?

That would be:

     (43.8 GWh x 1000) / 10.95 MWh = 4,000 panels.

If as stated above, each panel weights 19 kilograms, the total weight would be:

     19 kgs. x 4,000 = 76,000 kgs. or 76 metric tons.

So, in summary, one ton of uranium would produce approximately as much as 76 tons of solar panels.

1. The above calculations do not include the material used to build the actual nuclear reactor nor does it include the material required for the solar inverters. Also, for simplicity, the inefficiency of the inverters is not considered above.
2. Sure, it could be argued that at the end of its useful life the material in the solar panels can be recycled, but still the difference in material utilization is significant.
3. Other nuclear technologies in the drawing board could require less material to produce the same amount of electricity.
4. Fell free to make your own calculations and share your results if they are significantly different from the ones presented here.


Labels: , , , , ,

Friday, April 18, 2014

Renewables for Australia

Let's make our homework at what it would take to convert Australia to 100% renewable energy.* Not to make the exercise extremely complex, let's simplify it a bit by using only solar photo-voltaic (PV) in our calculations.

According to the IEA (International Energy Agency) Australia's electrical energy supply in 2013 was 228,152 GWh. To convert this to average power consumption we divide it by 365 and then by 24 to arrive at a figure of ~26 GW average power consumption.

If we consider that the capacity factor (CF) of solar PV in Australia is 20%, then the solar PV capacity that needs to be installed is:

26GW / 0.20 = 130 GW.  At $2 dollars per watt that would add up to $260 billion dollars (~$11,000 per person).

Let's also consider that at peak hours, Australia actually consumes 50% more than the average power and thus their typical peak consumption would be 26 GW x 1.50 = 39GW.

This means that, say, at noon in central Australia, we would have a surplus of 130 - 39 = 91 GW.

Thus, at many instances during the year most of the solar capacity would have to be disconnected to prevent destroying the electrical grid. This would mean that the effective capacity factor of solar would be considerably lower than 20% and thus more capacity would need to be installed but this would make the excessive production at many instances during the year even more problematic.

On the other hand and obviously, during the night there would be no energy production.

So, OK, by themselves the solar panels would not be able to supply the energy Australia requires but we can always use storage to smooth the power delivered.

Considering that in winter days are shorter let's add enough storage for 14 hours of the average consumption. That would be 14 x 26 GW = 364 GWh. 

Considering Tesla S grade batteries for the above, a total of approximately 2,330,000 tons of batteries would be required. The above would represent ~100 kgs per person. Sure, lithium batteries are among the lowest weight technology, other chemistries would be heavier.

According to IEA's latest electric vehicle report, the cost of this type of battery could reach ~$200 dollars per kWh by 2020. That would represent a total cost of ~$73 billion dollars. Sure, other chemistries might be less expensive. This would represent ~ $3,100 dollars per person. 

Adding the panels ($11,000) plus the storage ($3,100) gives a total of $14,100 per person. Sure, this is only the upfront investment. Every so many years the batteries would have to be replaced, as well as the panels. 

However, the above system wouldn't provide reliable electricity on an annual basis, as we know the insolation in Australia is relatively low from April to August. More storage would make it somewhat more reliable but the total cost would increase. 

Feel free to make your own calculations and share your comments if you get different numbers.

* We are considering only electricity which is a fraction of Australia's total energy consumption that includes fuel for transportation, for industrial processes, etc.





http://www.gaisma.com/en/location/sydney-au.html   (data for individual cities).

Labels: , , , , , , ,

Tuesday, April 15, 2014

Energy: Let's Do Our Homework

Energy is a complex subject in which many variables intervene and thus we do have to make our homework to choose wisely.

In the energy discourse we still see oversimplifications in which energy is divided into "dirty" and "clean." Discussions at that shallow level are not useful for establishing energy policy or even for educating the world on the difficult decisions we have to make.

With this article we want to motivate a quest for deeper understanding and the application of more reason and less feelings in this all important subject.

Let us first start by stating that there is no such thing as clean energy. When considering their full life-cycle, even the cleanest sources (hydro, wind and nuclear) have greenhouse gas (GHG) emissions and create other types of wastes that impact the environment. So, here are some of the things we should be asking ourselves:

1. What are the carbon emissions per kWh of the specific energy source (including all processes from cradle to grave)?
2. Is the energy reliable?
3. If it is not reliable, how are we going to compensate for its unreliability (other reliable energy will cover the lulls or would storage be used)?
4. If other forms of energy cover the lulls, then these emissions need to be considered in the emissions of the "system."
5. If storage will be used, we also need to consider the GHG emitted in the cradle to grave processes of the storage technology and add it to the emissions of the "system." Also, how many hours / days / weeks of energy do we plan to store? How much storage area would be required for the banks of batteries or other storage technologies? What is the leasing cost of this space?
6. Emissions are obviously not the only variable we need to be concerned about, resources utilization and costs have to also be high in the list.
7. What are the capacity factors of the different technologies in the specific place where we are planning to locate them?
8. Is it advisable to combine several types of renewable energy to somewhat compensate for the peaks and valleys in electricity generation? If so, say, how much solar capacity and how much wind capacity should be installed?
9. Should we go "all out" for a particular technology or only as much as makes financial / environmental sense?
10. Could climate change seriously modify our design assumptions in the short / medium term (e.g. less / more wind in a particular place on Earth)?
11. How much intermittency can the current grid absorb? Are additional investments required in the grid so it will be able to handle high penetrations of intermittent energy?
12. What type of investments would achieve the most bang for the buck (in other words, the best reduction in emissions)?

The above questions are just to get the conversation started.

The next step would be to model the complete system and calculate (among many other things) these two all important parameters:

1. Cost per kWh of the generated electricity.
2. Emissions per kWh of the system.

If either of the above is too high, we may need to go back to the drawing board until an acceptable system is designed.

Again, the purpose of this article is to make people realize that energy is a very complex subject and it is better to leave it to the engineers to design energy systems. Many times well intentioned but naive persons want to lead the energy discourse and this can take us to the wrong results: high cost / high emission systems.

Thank you.

Labels: , , , , , ,

Monday, April 14, 2014

Not Because They Are Easy, but Because They Are Hard

Drastically reducing our fossil fuels (FF) use without destroying the world economy and shoving most of us into a life of utter poverty is probably THE most difficult challenge humanity has ever faced.

Those that say this transition will be easy, are making a disservice to humanity. It WON'T be easy. Period.

Today, ~82% of our global total primary energy supply is delivered by fossil fuels. Consequently, the global infrastructure is built around them:
   1. Motor vehicles.
   2. Fueling stations.
   3. Air travel.
   4. Factories.
   5. Power plants.
   6. Pipelines.
   8. Maritime transportation
   9. Building space heating / water heaters
   10. What have you...

Some people believe renewable energy (mainly sun and wind) will "catch fire" just like the Internet and mobile phones did some years ago, but this optimism is misplaced.

Both the Internet, as well as mobile phones gave us the opportunity to do things we could never have done before, on the other hand, a replacement of FF by RE would not provide value to the final consumer, if at all, RE would be more expensive and less flexible. Besides RE, since it is not constant, requires FF most of the time to prop them up when the sun is not shining or the wind is not blowing*.

The annual capacity factor for solar PV worldwide today is ~15%, which (simplifying) means that 85% of the time something else has to produce the electricity, and that "something" is usually a fossil fuel plant.

We have also been somewhat deceived by "Moore's Law" on how fast technological improvements can take place. Integrated circuits (ICs) today have more than one hundred million more transistors per unit area than those manufactured in the 1960's. However, ICs handle information, not loads of power, so we are talking about very different things. The advances in power production and efficiency move at a snail's pace. Say, if the energy efficiency conversion of high volume solar PV is today ~14% (in other words, the percentage of the sunlight striking the panel that is actually converted to electricity), when will it reach 28%? The answer is probably never.

So, what we are currently asking of humanity is to spend many trillions of dollars to essentially end worse off than today (sure, if everything turns out right, with a lower carbon global economy). However, for the final user low carbon electricity "tastes" the same as FF electricity but is more expensive. We also need to understand that electricity is only a fraction of our total energy consumption and the energy used in transportation and industrial processes is more difficult to replace with low carbon alternatives.

So, bottom line, is the transition possible?

The answer is yes, but it will require sacrifice, more sacrifice and yet more sacrifice.  It would require a massive nuclear build up equivalent to what France already did, but in most of the other countries in the world.

We should, however, differentiate what is possible from what is probable and so far there is nothing in the pipeline, so to speak, that will reduce our absolute use of fossil fuels.

2013 was the all time record for emissions. What will be the results in 2014? In 2015?

The first step to start solving our emissions problem is to confront the brutal truth: whatever we have been doing is NOT working. Our emissions not only are not dropping, they are INCREASING.

Let's stay tuned.

* Some RE lobbyists state that RE is has already achieved grid parity. This is not accurate. Here is why:

Labels: , , , , , , , , ,

Tuesday, April 08, 2014

Emissions and Renewable Energy

Does Renewable Energy (sun and wind) reduce emissions?

The short answer is: in theory it does reduce emissions.

But what about in practice?

Here things look quite differently. Let us show why with an example.

This is obviously going to be an over simplification, but please bear with us.

Let's consider an isolated country that decides to go all out for renewable energy, in this case wind turbines.

Let's make our estimates below with a wind annual capacity factor of 30%.

So, this country will get 30% of its energy from wind turbines and the rest, say, from natural gas powered plants.

The emissions of the turbines are ~ 12 grams per kWh.

The emissions of natural gas plants are ~ 469 grams per kWh.

Thus, the emissions of the whole system would be:

     (0.30 x 12) + (0.7 x 469) = 332 grams per kWh.

If we replace natural gas by coal (with 1001 grams per kWh) then the numbers look less attractive: 704 grams per kWh for the system.

The same exercise with solar photo-voltaic would result in larger emissions since the capacity factor of solar is even lower than that of wind.

Sure, it could be argued that renewable energy could be "stored" but for the most part those systems have not been deployed and would require important investments and additional emissions during their manufacture.

Conclusion: in real life we have to consider the emissions of systems, not of individual components and when the system is considered, the ability of renewable energy to reduce emissions is limited.

This is one of the reasons why German emissions per kWh remain stubbornly high in spite of all the renewable capacity they have installed.

Labels: , , , ,

Monday, April 07, 2014

Types of People in the AGW Discourse

The Anthropogenic Global Warming discourse is supposed to be happening between the Deniers and the Believers but this is an oversimplification that does not fit well into the actual reality, so we are presenting below a more useful classification.

1. The Deniers: they don't believe AGW is happening and no evidence will make them change their mind.

2. The Believers: they believe AGW is happening but they have their feet on the ground.

3. The Naivers: they believe Renewable Energy (RE) will replace fossil fuels (FF) and save the day.

4. The Black Swanners: they believe in AGW but at the same time understand that humans will not voluntarily reduce their standards of living. Thus humanity will NOT reduce their FF consumption for many decades to come. The way out? A serious black swan event that will solve the emissions problem "through the back door." Examples:
     a. A gigantic volcanic eruption in Indonesia.
     b. An ebola like virus that drastically decimates human population.
     c. What have you.

5. Gamblers: they do believe AGW is happening but decide to wait and see. There might even be some unintended positive consequences of climate change. If nothing else, their investments in Greenland may become more valuable.

6. Opportunistic: the ones that make loads of money by selling the RE to the Naivers (above).

7. Liars / Lobbyists: what they believe in their heart is irrelevant. They follow the money and fully support their sponsors no matter how much they have to bend themselves backward to seem reasonable.

Framing people is never good, but it is certainly better to frame them in SEVEN camps rather than limit them to only two.

We hope the above classification adds something positive to the energy discourse.

Labels: , , , ,