JGZ

The EROEI (Energy Return On Energy Investment) ratio of any technology simply shows one thing: Wether the technology is an energy source (EROEI >1:1, so more energy is produced by it than is used to build and run it) or an energy sink (EROEI <1:1, so less energy is produced by it than is used to build and run it). Examples of energy sinks are ethanol made from corn (EROEI of about 0.85:1) and PV (Photo Voltaic) in Germany (EROEI of about 0.95:1). If the technology has an EROEI of about 1:1, it simply is a means to re-label fossil energy sources to "reneable" ones. Examples of energy sources are petroleum wells in Saudi Arabia (EROEI of about 30:1) and CSP (Concentrating Solar Power) in north Afrika (EROEI of about 60:1).

If the technology is an energy source, and its EROEI ratio and life-time are known, one can calculate how fast it can be deployed/scaled-up sustainably. Lets say we would like to grow PV sustainably in an area of insolation where PV can achieve an EROEI of 2:1. We know the life-time of PV cells is about 25 to 40 years, so lets assume an average of about 32 years. From that we can tell, that we could get twice the energy we invested out of PV after 32 years. Since the intial investment was made with fossil energy which would be compensated after about 16 years of operation, we could only sustainably renew our PV installation during the remaining 16 years of operation. Since the new installation does not use any fossil energy sources, its production could then be used to double the installation size every 32 years. So we would not get any sustainable growth within the first 32 years, but after that we could double the installed PV capacity every 32 years. However, if we did that, we would not have any of the solar energy left for anything besides the production, installation, and operation of new PV plants. So it would be a rather pointless exercise.

This shows us, that we need renewable energy sources with a much greater EROEI ratio than 2:1, if we want to grow reneables within a reasonable time-frame and use their generated energy at the same time.

Lets run through an example based on PV in southern California, where it might achieve an EROEI ratio of about 4:1. There it would only take about 8 years to break even, after 16 years we could have doubled, and after 24 years quadrupled the PV installation. At the end of the life time of the first plant, we could end up with an eightfold increase of PV power generation capacity. Now this already looks a lot better than our previous example, right?

However, even in these very good circumstances it is not nearly good enough to compensate for dwindling oil production and to combat climate change.
Why? Our initial installation is based on fossil fuels, of which we can only allocate a tiny amount to building renewable energy sources, without breaking the rest of our economy. So our initial installation size is very limited, but we still have to meet enormous generating capacity goals in the near future.

Ten years from now we will have to have replaced coal with renewables, and another 15 years later we would have to have done the same with oil, followed by natural gas another ten years after that. At the same time we will have to make enormous progress on energy efficiency to flatten our consumption at the current level, and find a way to extract a good portion of the CO2 we have put in the atmosphere in the past. Because until we have finished the transformation of our econonmy to run on renable instead of fossil energy sources, we will still add more CO2 to the atmosphere. However the current level is already at 380ppm, but we need to get below 350ppm really quickly to get last century's favourable weather patterns back, preferably before Greenland's and Antarctica's ice has slipped into the sea and the enormous amounts of frozen methane are released from the permafrost.

Now lets take a look at CSP plants. Depending on whose calculations you want to believe and where the plants are built, CSP has an EROEI ratio of about 30:1 to 70:1 over its life time of about 30 to 40 years if deployed in deserts with good insolation. So lets assume an average EROEI of about 50:1 with an average life time of 33 years and 4 months. This would mean that CSP generates the energy it takes to build, install and operate in only 8 months, within 16 months we could have doubled our installation, and within two years we could quadruple our installation. In the lifetime of the first plant, we could achive an 281.474.976.710.656-fold increase in production capacity.

If we started out with a modest 50MW plant, within only 14 years we could build enough CSP power generation capacity to power all of humanity and completely replace coal, petroleum and natural gas as energy sources. Of course in reality there would likely be other factors limiting the rate at which CSP could be up-scaled, meaning that not all of the CSP power would be used to build new plants. So we would use the surplus CSP power to reduce the use of fossil energy sources.

Some of these other limiting factors might be: available capital, available numbers of engineers and skilled workers, transmission line capacity, construction materials, etc.

I would like to point out that most people vastly over-estimate the potential of most renewable energy sources, and under-estimate the scale of the task we are facing when it comes to energy. Building our future energy supply is by far the biggest challenge humanity has ever faced. To meet it, we would have to build one new 1000 MW nuclear power plant every day for the next few four decades, and we are already a decade behind schedule to meet the moderate goals of the IPCC. If we actually did this, we would run out of uranium within a few years while turning our planet into a toxic nuclear waste dump. And of course at the end of the 4 decades, we would have to start over, as the oldest plants would approach their end of life by then.

Concentrating solar-thermal power (CSP) ist the only technology currently available which has the potential to solve our energy and climate problems. Hopefully it will be complemented in the near future by new technologies.

For more info on this, I recommend an excellent presentation by Dr. Nathan Lewis of the California Institute of Technology (CalTech).

He also gave a very good presentation on a possible future technology to solve the energy problem, which his team is working on at CalTech.

Note that Dr. Lewis seems to have missed the possibility of thermal energy storage used by modern CSP plants.

For the oxygen unit, I pretty quickly realised, that the prices don't differ that much. If you want one with a demand valve (enabling patients to breathe almost 100% oxygen, compared to about 75% on a non-rebreather mask), the offers from DAN Europe (the diver's alert network) are very good value and the quality is very high.

For AEDs there are much better devices than the ones DAN had on offer, and after a little bit of research on the net I decided to go for the Zoll AED Plus. This is quite costly, but it has some unique features, like a sensor that measures both frequency and depth of CPR chest compressions and a device lid that doubles as a head rest which holds the head in the right position to keep the airways open. It also gives both verbal and visual instructions for CPR.

> Our Kilbirnie meeting is next Wednesday 4th June at
> the corner of Kemp & Tacy Sts, Kilbirnie. Come after work and throw
> something on the BBQ for a shared meal. We have an excellent guest
> speaker, and all are welcome.

I wish I could be there. I can't wait to go diving again, too.

I'm currently very busy with paperwork to get back into the German social security system, which is a couple of days worth of work. German bureaucracy at its worst.

At the same time I'm trying to get my flat back into a liveable state. The other day I got my waterbed repaired, but there is still a lot of tidying and cleaning to do. There is an 18 months old layer of dust on everything. Next time I'm away for a longer period of time I will certainly cover everything with big sheets.

Claire has started working for my dad's company, so at least she is not distracting me all the time with moans of "I'm bored, I want to go out" all the time.

Tomorrow I will have to drive down to Frankfurt Airport (4 hours drive) to collect my computer monitor, which I had sent over with Qantas Freight but arrived at Lufthansa Freight. For some strange reason they seem to be unable to forward it to Paderborn Airport (40 minutes drive).

The car in Wellington has not sold yet, so I have just lowered the reserve price by $500. I'll keep reducing it by $250 a week now until it sells.

As expected, PADI (or the postal services) are taking ages to send me my instructor pack and certification card, too. The envelope that arrived here three days before we left NZ turned out to be the member forum participation certificate.

During our ten hour interval between flights in Sidney we looked at the Royal Botanical Gardens, the Opera House, and Government House.

In Singapore everyone had to get off the plane with all the carry-on luggage (which in our case was about 30 kg) and wait in the airport for half an hour, while customs officers checked the plane and every passenger for drugs.

In Frankfurt our flight to Paderborn was delayed because of a strike and it took the airline a while to find a crew that was actually working. Fortunately our checked luggage (three really big suitcases each, with a combined weight of 138 kg) was checked through from Wellington to Paderborn. Otherwise it would have been close to impossible to catch this domestic flight.

But in the end we arrived exhausted and very very tired, but safely here in Soest.

So far I have completed my PADI Specialty Instructor courses for Oxygen Provider, Wreck, Underwater Navigation, Digital Underwater Photography, Underwater Videography, Drysuit, Enriched Air, Search & Recovery, and Diver Propulsion Vehicle with my Course Director Tony Howell of NZ Sea Adventures. I also completed the DSAT Gas Blender course. But I have not made my application for these qualifications to PADI yet, because I want to do two more Specialty Instructor courses before leaving Wellington: Deep, and Night diving.

I have already completed my Emergency First Responder Trainer course, so I can now teach first aid and CPR courses, too.

I'm also getting my DSAT Gas Blender qualifications this week.

So from Wednesday I'll be going through another PADI Instructor Development Course, which will last 10 days, followed by the three-day IE. If it is anything like the last IDC, I'll be working/studying an average of 17 hours per day, so don't expect me to reply to any kind of communication attempts for the next two weeks.

Currently the plans are to install about 6000 MW (Mega Watt) production capacity world wide by 2013, currently we have about 450 MW capacity. 6000 MW production capacity means about 43.8 TWh/a (Tera Watt hours per annum). This is roughly the current electricity consumption of 12 million households or 48 million people.

However it is no where near enough, because we are currently experiencing a phenomenon called peak-oil, which simply means that in the next 20 to 40 years we will loose roughly 80% of our annual energy production capacity, as we are running out of easily accessible petroleum. This is currently the most serious problem facing the western world today, it will have enourmous impacts on almost all aspects of our lives: from our food production to our transportation. If you have not done so already, I strongly recommend you read LATOC. For Germany alone another 500 TWh/a by 2020 and 1300 TWh/a by 2040 will be needed to replace petroleum. For comparison: Germany currently produces about 530 TWh/a, its combined photo-voltaic electricity production is only about 3 TWh/a (2007).

Most alternative energy sources (like many bio-fuels for example) are not really energy sources at all, but energy sinks. That means they take more energy to produce than they release when used. This ratio is called Energy Return On Energy Investment, or EROEI for short. Even those alternative energy sources, that actually do have a positive EROEI (like "solar" photo-voltaic panels and "wind mills") offer no where near the EROEI of about 30 to 1 that petroleum has to offer. CSP however offers an EROEI between 30 to 1 and 80 to 1 for electricity alone. So during these plants life-time of 30 to 40 years, they pump out 30 to 80 times as much energy as was used for their construction, plus enourmous amounts of desalinated fresh water and process heat. This is a much better EROEI than that of petroleum. And this is also the reason, why CSP is in my eyes the only alternative energy source available to us in time to save our great western culture.

Please have a quick look on http://www.solel.com/faq/ for a short introduction to the technology before reading on.

 

The biggest problem is, that we are running out of time very quickly, and there is not a single technology which we could install in big enough quantities in so little time, except for CSP.

As Tom ("great769") on the LATOC forum put it: "Alternative [energy], could have worked but we would have had to start back in the 60's or 70's, while husbanding our oil resources. There will be and is a big surge to solar/wind, in the next few years, but even if we could convert 1% per year to these , which would be a hugh task, it would take decades to convert 50%. The world does not have decades, we have only a few years at best, we can't even breed enough horses to replace local delievery transport in that time nor bulid trains, before the crunch, even a WW2 [production] effort would come up short at this point."

This is certainly true for most renewables, but not for CSP. These plants are extremely scalable and can be easily and quickly mass-produced. In the areas where they are most viable (deserts) there are usually vast amounts of the raw materials needed to build them available locally, and so is the needed process-heat (once you have put the first one up, it can provide the heat for glass-, aluminum- and steel-production of subsequent plants) to convert them to the needed refined materials.

Also, we do have a few decades to do it. Between 2010 and 2040 we will have to replace an average of about 3.8% of our current oil consumption with alternatives each year. This is assuming that we will still need an annual increase in energy production of about 0.46% per year to keep our economy going. It also does not take the huge efficiency increase (at least 30%, up to 80%) into account, that the electrification of most currently oil-driven technology (like cars) would bring about.

This would mean replacing 1142.45 million barrels of annual oil production capacity with 1808.37 TWh electricity production capacity per year. To do this with CSP only, we would need at least 247722 MW new production capacity per year.

Now what does it take to build that kind of capacity per year with CSP?

Well, CSP plants currently in the planning stage have a typical production capacity of 200MW or 1.46TWh/a electricity, 8000 m³/a of desalinated water, and a considerable amount of process heat which can be used for industrial purposes or converted into thermal cooling to replace electrical air-conditioning. So we would need to build about 1240 of these 200MW CSP plants per year to meet our annual goal of 247722 MW, which would also supply us with almost 10 million m³ fresh water production capacity per year.

Each one would be made from about 560,000 parabolic trough mirrors (2.04 million m² of mirrors), 57,000 solar receiver tubes with a total length of about 230km, 115 kt of salt (60% NaNO₃ and 40% KNO₃), and whole lot of metal and concrete for structures and buildings. Each plant would need about 8 km² of desert. Currently (before the start of mass-production) it would take about 4000 man-years (4000 people working for one year) to build.

Each one would cost about 1167 million dollars to build. If we assume a 7% interest rate per year for the initial investment and amortisation within 15 years, the operating costs during that time would come to about 220 million $/a (incl. insurance, etc.), which could be covered by a price of about 0.11 $/kWh and 1$/m³ of fresh water. So the building and financial costs would be paid for after 15 years.

Then the price for electricity could be dropped to 0.028 $/kWh for the remaining 15 to 25 years of its life time, which gives us an average price of 0.069 $/kWh. So CSP would become cheaper than petroleum when the latter crosses the 110 US$/bbl mark, ignoring the fact that electric technology is much more efficient (so cars would have been cheaper to run on CSP electricity instead of gasoline for some time now).

To get the required 1240 plants per year built, we would need a construction force of about 5 million people world wide, if no mass-production is used. Keep in mind that towards the end of this 30-year project the first plants would soon need to be replaced, so these jobs would mostly be permanent.

Each plant would create about 50 permanent jobs for operation and maintanance, which means about 60,000 new permanent jobs per year.

It would certainly be a big project, but I think this is achievable and could possibly even be scaled up further to bring better living conditions to the third world and developing countries and/or in case we run out of petroleum even faster than predicted.

For more information, go to the TREC/Desertec website and don't forget to show your support by giving them your voice.

More relevant links are in my links collection (menu).