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What do the numbers: 6.6, 6.7, 6.9, 8.5 and 14.2 have in common? All give the proportion of renewable energies (RE) at the Primary and Final Energy Consumption in Germany in 2007 in percent. Which figure, however, is correct? The BMU, German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, based in Berlin, Germany (*) knows it. In principle,all of these figures are correct. One has only to put them in the context.
6.6 % is the share of renewable heat in total energy consumption
6.7 % is the share of renewable energies in total primary energy consumption
(calculated in accordance with the so-called efficiency method)
6.9 % is the share of renewable energies in fuel consumption
8.5 % is the share of renewable energies in total final energy consumption
14.2 % is the share of renewable energy in total gross electricity consumption
In BMU text then reads: "... In the year 2007, the use of renewable energies in Germany a further boost. The contribution of renewable energy in total primary energy consumption in Germany in 2007 amounted to approx. 8.5% (2006: 7.5 %)..." That sounds all well and good, and like "high tech". But can you really be proud of it and what orders of magnitude hide behind these percentages? Especially when you have to deal with percent information, one should always ask: Who or what are the 100 percent? In order to improve comparability for the following information, all following figures are converted to TWh, which are billion kWh.
The “sum up” of all the figures is: With 152.4 TWh, the biomasses are far ahead of all renewable energies in Germany (total 222.0 TWh). The largest share absolutely have so called: “biogenic solid fuels (households)”. The renewable energy in Germany is mostly simply nothing else than wood. That said, the biogenic fuels (industry) and the biogenic share of waste in this regard also have their additional shares. Somehow, the "public opinion" and the "published opinion" in Germany are conveying other pictures. What may be the reason?
Shares of renewable energies in detail
Heat generation by renewable energies
In the heating applications, the entire biomass (solid, liquid and gaseous biomass, sewage and depot gas, biogenic waste) with 84.3 TWh stands for the largest share of heat supply. The shares of solar and geothermal heat with 3.7 TWh and 2.3 TWh is still clearly subordinate. The use of firewood in households increased by 8% from 2006, the demand for heating pellet was in the last year no longer as strong as in 2006.
Renewable energies in fuel consumption
In 2007, there was an increase in biogenic fuel sales. It increased to 44.4 TWh. In addition to the remains dominant sales of bio diesel of 32.9 TWh, 7.9 TWh vegetable oil and 3.5 TWh bio ethanol were registered for the past year. That's according to BMU report, 6.9% of fuel consumption relative to the entire road traffic and 1.2% relative to total primary energy consumption. Anyway, a step into the right direction.
Electricity generation by renewable energies
Wind power last year was accounting 39.5 billion kWh for electricity generation. With a new installation of 1,625 MW in 2007, Germany is "... still one of the best in the world ...". This is only relative, when compared with the current champions United States (5,244 MW), Spain (3,533 MW), China (3,449 MW) and India with 1,730 MW. Electricity generation from hydro power remained at 20.7 billion kWh largely stable. The conversion of biomass rose to 17.4 billion kWh. Together with landfill and sewage and the proportion of biogenic waste, the entire biomass for electricity generation, with 23.8 billion kWh first time was coming ahead of hydro power. Photo voltaic rose by approx. 60% to 3.5 TWh and a proud 0.6% share in total gross electricity consumption. The share of geothermal energy for power generation is equipped with 0.0004 TWh in 2007 is still negligible.
Let us finally take a look at the employment effect. In Germany, one often hears about: "... a worldwide leading technically-profile industry with over 200,000 jobs created...” (EUROSOLAR, May 30, 2008). In reality, the biomass bears the burden with 96,100 employees and the most part in gross employment, followed by the wind energy with 84,300 employees, 50,700 in solar energy, 9,400 with hydro power and 4,500 with geothermal. Not to mention the 4,000 people whose jobs have been created by: "... the provision of public and private resources in research and administrative imperatives ..."...
Now everyone can calculate for yourself, what trends lay in these figures. One can also think, what this all could have to do with hydrogen and fuel cells. The questions are: Where will the sustainable future be and how do we to get there? It all remains in any event exciting. I sincerely hope, we do not have to wait to long for it.
(*) The development of renewable energies in Germany in 2007 as at March 2008, Publisher: Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, Berlin, Germany
I have studied the energy situation in Germany for many years, though not in detail because my knowledge of the German language has unfortunately deteriorated.
If you are saying though or trying to say that a monumental scam is being perpetrated on the German people and others by the Energy-Elite and politicians in Germany and Brussels, then I am in full agreement. The so-called intention to replace nuclear by wind and other renewables is ridiculous, although amazingly some high-level and/or influential academics have unfortunately bought this silliness. Yes, many people in that country - and perhaps a majority - do not want to have anything to do with nuclear, and their wishes should be respected, but clearly nuclear or coal will have to provide all or a large part of the German base load.
What about gas? Yes, what about it! I once gave a talk in Germany or somewhere in which I said the more gas contracted for from the Soviet Union - now Russia - and the larger the pipes used to transport that gas the better, but the energy experts in Germany at that time preferred the wisdom of (President) Ronald Reagan, just as now they prefer the wisdom of 'almost' President Al Gore. The price of gas though will change a few minds about the use of that resource.
What is my interest in this? With the crazy intentions of the European Union and its Energy Directorate, and the degree of electric (and gas)interconnectedness in Europe, the wrong energy economic decisions in Germany will place a financial burden on my good self. A burden that I am not anxious to support, although if the persons who voted Sweden into the EU also have to support it, my disgust will be somewhat relieved.
Jim Beyer 6.11.08
Germany seems ripe for PHEVs. They drive a lot and import all of their oil. They have built lots of wind and solar electric generation, which would be able to apply this intermittent power to PHEV chargers. Last, but not least, the gov't would likely hand over some healthy subsidy to help pay for them.
Jeffrey Anthony 6.17.08
Ferdinand E. Banks --
Why does the advancement of renewable energy always have to be viewed by you and others as a "monumental scam". There are so many posts on these EnergyPulse comments that mischaracterize both the benefits and the limitations of renewable energy generators such as wind turbines, that it is almost not worth reading these anymore.
Renewable energy is not promoted as a baseload generating technology and is best understood when viewed as an energy resource. Being a variable output generating technology, no credible authorities are promoting it as a means to repace baseload CAPACITY provided by nuclear or coal plants anytime soon -- but rather as a way to back down the ENERGY output of generating units, typically natural gas and coal generators (while still replying on them in peak load conditions as available capacity resources) -- but at the same time reducing emissions when wind generators are producing electricity to lower the amounts of harmful pollutants into the atmosphere.
Only the most jaded anti-wind conspiracy theorists fail to recognize the benefits of renewable energy and wind power generators for what they are -- energy generators, not baseload generating technologies. Read more at: www.20percentwind.org (Chapter 4 of the full report)
Jeff Anthony American Wind Energy Association
Don Hirschberg 6.17.08
I don’t know how to use these numbers. They strike me as more obfuscational than edifying. They hark back to a previous query of mine: Why are Germans designing wind farms for 20% capacity factors?
Mathew Hoole 6.17.08
To Jeffrey Anthony.
Sorry but I am one of those that believe wind and solar are a 90% sham. I see geothermal as having potential.
To explain why I believe wind and solar is a 90% scam is because EVERY person I have talked to in Australia who supports wind and solar both believe and will vote for a political party that will replace coal power stations with wind and solar farms.
I repeat EVERY person I have spoken to in Australia who likes wind and solar believes wind and solar can replace baseload coal.
There are several "right" solutions or potential soluitions to replace coal power stations or other polluting baseload power station. Wind and solar are not baseload solutions.
If you want to use solar for hot water and wind to pump water or other similar use - I don't have a problem.
I do believe the solar industry, wind industry and environmental activists in Australia are either being selectively gullible or deliberate deceivers.
If the opposite were true, everyone would know that wind and solar are not suitable replacements for other more conventional baseload energy sources.
I have no interest in seeing wind and solar industries destroed. I also have no desire to see the global and Australian economy go up the spout because of blatant misinformers.
From the Australian perspective renewable industries have at least "let it ride" or exploited this misinformation.
The record needs to be set straight about renewables and baseload generation. The Renewables Industries need to be accountable to do that.
The global community NEED and DESERVE to know what wind and solar can and can't do. And that knowledge should be what the wind and solar industries should be founded on.
Len Gould 6.18.08
From Website of Independent System Operator (Grid and Market Manager) for Ontario, we learn that on June 17, 2008, Ontario had 771 MW of wind generation connected, of which only 404 MW were operating at all. From that 404 MW connected capacity, the grid received an average of 72.17 MW for the day (Max 121 MW at Noon, Min. 20 MW at 11:00 PM) for an average capacity factor of 17.86% if only the 404 operating MW are counted, or 9.36% if the 771 MW connected are counted.
We also learn that for the month of August, 2007, the (only 396) Total reported MW of Wind generation achieved an average 19% capacity factor. Insufficient detail is available to determine exactly what it was doing at the peak hour of that peak month, but given how winds work around here on hot summer days, it's safe to assume significantly less than 19% of connected capacity, meaning it is next to pointless as "replacement" for coal burners, often displacing baselaod nuclear and hydro generation for the small amounts it actually does run.
I strongly disagree, however, with the above comment which lumps solar and wind into the same category. Solar thermal in good areas, especially with relatively cheap thermal storage and perhaps natural gas-fired auxiliary heat for cloudy days, is scaleable and predictable and economically competitive especially with gas turbine peakers, and it's peak output largely coincides with peak demand.
Mathew Hoole 6.18.08
Len, a few points
1. I live in Australia which is considered the best continent for solar energy.
2. I have had hot water solar panels on my roof. They were useless in winter, and useless in summer when thickly overcast. Although not optimally placed on my roof they were not in a bad location. My booster button was used around 1/2 the year every year.
3. In the month of February this year the entire east coast of Australia (where most of the population is) was coverd in cloud for 10 days straight. This in a 1 in a hundred year drought. I doubt there is a supplemental storage system that can sustain most of a nation's population over such a period of time.
4. Australia has a great tendancy for extreme weather. We could have 5 years of severe drought with 5 years of severe flood. I wonder how effective solar energy would be if most of the continent was covered in thick cloud for the greater part of a month. I imagine backup storage would be exhausted AND would be unable to regeneratge.
5. If backup storage plants (like coal, gas, nuclear or other) are required to backup severe and prolonged energy shortages from solar (and this is somehow economically competitive), why bother with solar at all. Surely just by having a gas, coal, nuclear or other energy plant running reliably 24/7 would be more efficient than having such plants available on standby (as well as temporary storage plants) to supplement intermittant solar energy.
5. An essential prerequisite to be a Baseload Energy Supplier is reliability. Rain droughts are devastating to a nation. Preventable Energy Droughts would be more damaging and to be quite frank, stupid!!!
I'll say again.
In Australia Wind and Solar industries either deliberately exploit misinformation on how their industry fits with baseload energy or "lets it ride". With global warming (Climate Change) in fashion in Australia and the public in a panic, wind and solar industries should be far more accountable on what they (and what they don't) tell the public.
Len - If I am somehow off track with solar (thermal or otherwise) please point me in the right direction.
Ferdinand E. Banks 6.18.08
Good for you Mathew. I've taught at 5 or 6 Australian universities, and one of the problems in that country is that there are not enough competent energy economists or commentators to make up a good poker party. There are only a couple of gentlemen who are capable of putting the television audience right on this matter of what renewables can and can't do. Instead they listen to people like Jeffrey who get their scientific information from comic books and CNN. I certainly would like to see your post circulated throughout the world, and if I rewrite my textbook I hope that I can remember to include it.
It's different in Germany though. There are many energy economists in that country, but almost all of them refuse to say what should be said about nuclear and renewables because they prefer more money to less: academics who sound off about the craziness of attempting to replace nuclear with wind and solar run the risk of selling apples on the Reeperbahn (or something like that). Let me say however that with the price of electricity moving the way that it is moving at present, it is only a matter of time before a large majority of Germans come to the conclusion that inexpensive electricity makes more sense than the other kind.
But please understand me Jeffrey - I am NOT against renewables. Obviously they will have to be used because the people who want them used still have considerable political power. Sure, I'm a great economics teacher, but even so I'm not a complete fool. A suboptimal solution is going to have to be accepted in this matter, and as long as that particular solution doesn't go completely off the rails, those of us who think that we know best because we can manipulate supply and demand curves are going to have to adjust. Even so, I find it genuinely tiring that you and your friends cannot read and try to understand the lesson in the first paragraph of Len Gould's comment.
Mathew Hoole 6.18.08
Thank you Fred, however please run a spell check first. I should get into the habit of doing that.
I would like to see renewables have a proud and prosperous future. However that foundation should be based on what they can and can't do (case by case).
I didn't even mention above how wind and solar 1. are effectively useless in high density housing, commercial or industrial centres i.e. how many windfarms or solar panels could you put on a high rise commercial centre??? 2. will compete on urban fringes with housing, farms and forests (or reforestation) 3. have a very poor energy supply/space ratio i.e. how large a solar farm would be required to match the output of a coal or nuclear power station.
These are not small issues if you are going to develop en masse large scale wind and/or solar farms.
Mathew Hoole 6.18.08
I don't know why the formatting did not work that time??? :(
Todd McKissick 6.18.08
Mathew, I have to strongly agree with one thing you said. Evaluating renewalbe on a case by case basis is the only way to get any useful data. Too often they are lumped together as one form of energy. What works for a farm won't work for a city dweller or for someone living by a stream. In addition to that, somehow people insist on tossing small scale renewables in the same basket as large utility scale systems.
The mass media will rarely report on anything but solar PV, wind and the odd biofuel. If that's where you're getting your news, then you should look elsewhere because those deserve the intermittant label and can't support much of our needs by themselves.
There are many others out there, both existing and out soon, that satisfy more of your requirements. Think of it this way, my modest rooftop receives an average of more than 250 kWh per day of energy in the form of sunlight and heat. Over the year, it only ranges from ~150 to 400 kWh. Why should I pay hundreds of dollars each month to buy around 50 kwh/day (total of electricity and heat)? Since I already expect to pay for a furnace, water heater and other equipment, why can't I just buy different equipment that can make use of that sun? Sure, Detroit and Seattle won't get as much, but much of Alberta gets the same and California get twice what I do. If some of us can make any money on it, we'll gladly oversize our systems to cover those 'high density' houses you refer to. However, there's more than enough energy available to support a residence of less than three stories, provided it can collect the sun. I don't consider this suboptimal progress.
Regarding large scale solar thermal plants using too much land.. If you include the mines, they use much less land. About half of the estimates I've seen put them at less land area than nuclear if the mines are again included.
fyi: You need to hit enter twice to get a space between lines in a comment.
Fred, As I understand it, those huge solar subsidies in Germany have only cost the consumer a small ($3 or $10) monthly charge. I'd call that cheap considering Freiburg now buys 1/15th of the electricity they used to.
Len Gould 6.18.08
Mathew: "I have had hot water solar panels on my roof. They were useless in winter, and useless in summer when thickly overcast. " -- ?? What particularly do uninsulated non-concentrating probably plastic water heater collectors in eastern Australia have to do with CSP solar power generation in the mid-western deserts of N America? With a heat-based solar generation system, why would backup be provided by buring fossil fuels in a separate generating station rather than simply used to heat the solar thermal storage medium directly in cloudy weather? etc. etc. etc.
It is blatantly nonsense "knowledge" such as this which completely frustrates me. For anyone with access to this media, learning is cheap and easy.
Mathew Hoole 6.18.08
If I am wrong please correct me and educate me.
I do want to make the following points. 1. In winter there is often less sunlight, and the sun is lower on the horizen. Those countries that don't experience this usually instead experience monsoon weather and experience thick cloud during the afternoon. Solar energy would have to suffer from this.
2. There is no sun at night. Energy storage would be required at night as energy would still need to be used at night.
3. Is it or is it not more economical to have energy sources close to where the demand for energy exists? I believe the further away the greater the cost.
4. Deserts get cloud cover too, but with less frequency. It is wrong to assume that if 1 desert is cloudy, other solar concentrated sites will not be cloudy. In wet periods in Australia it is not uncommon for the entire continent to be covered in cloud. The US although larger than Australia is not magically different. I have seen US weather reports where cloud covers much of the country.
Why do wind and solar advocates speak only in maximum terms and imply by tone that such maximums are regularly possible?
How much does cloud cover impact on solar energy generation?
Why doesn't the solar or wind industries compare their products using worst case scenario versus other power generation, rather than an average or maximum? It is the minimum scenario that society would probably have to deal with at least once a decade, and less than average 5 years in 10.
If a wind or solar farm promises a maximum of 150 terrawatts over a year but can only deliver on average 50 terrawatts per year, and in the worst year over the decade only delivered 30 terrawatts; then surely with a safety margin and common sense that 150 terrawatt farm could only provide 25 terrawatts with certainty, then this is how the farm should be measured. Speaking of averages and maximums is wonderful until there is an energy shortage. I wonder how frequently the rain or winter be blamed???
Len: How effective would you CSP Solar Power station in the western desert of N America be in winter with a week of thick cloud cover? Or in more freakish conditions 20 cloudy days per month?
I am not trying to be rude to you Len, nor am I trying to intellectualise myself via cynicism. I am simply trying to understand a baseload system that doens't seem to get regular supply for processing but still offers reliable energy to the end user.
Ferdinand E. Banks 6.19.08
Todd, hats off to the good decision makers and their foot soldiers in Freiburg, and apparently a similar environmental success story is taking place in Växsjö Sweden. Before I send apologies to the environmental movements in Germany and Sweden however for using expressions like 'scam' and 'bluff'' to describe their efforts to pull the curtain down on nuclear, I think that I'll wait until I've had a decent vacation, and then look at exactly what has taken place in those charming communities.
Len Gould 6.19.08
Mathew: "How effective would you CSP Solar Power station in the western desert of N America be in winter with a week of thick cloud cover? " -- Item: Season has almost nothing to do with concentrated solar energy collection at lower latitudes except to reduce air humidity content, which increases energy collection per hour. Item: cloud cover etc. are easily dealt with by applying heat from alternative auxiliary sources directly to the thermal storage material. All our calculation are based on long-term average net energy available from solar in specific regions, and the systems can generate cheaply enough to compete, now, expecially when the waste heat from generation or from low-insolation time periods can be exploited for domestic water heating or space heating, as in small distributed solar CHP systems.
It really isn't rocket science. I fail to see why such resistance.
Len Gould 6.19.08
"except to reduce air humidity content" should be "except to reduce air humidity content in winter"
I'd also note that if the system incorporates water and space heating with the waste heat from generation, then the further north or south of the equator it is installed, the more economically attractive it becomes. It's often easier to make an economic case for such a system in areas which have heavy heating loads than in subtropical climates where the waste heat needs to be vented to a hot humid outdoor environment, reducing efficiency and increasing costs.
Todd McKissick 6.20.08
Len and Mathew, It seems to me that many of the misconceptions going on may be because Mathew has less awareness of which type of systems apply to what size and geographical need. Here's a hopefully brief overview.
Solar is usually referring to PV unless dealing with experienced people on larg farm scale applications. This should only be called PV because it has almost no traits in common with other types of solar.
Concentrated Solar Power usually refers to a large plant in a high sun region (desert) using mirrors to collect lots of sun which is used as the 'fuel' for running an engine to make electricity. In many designs, this 'fuel' (aka heat) is most easily stored in a tank prior to being used. Obviously, this storage system provides a disconnect between the times when collecting and generating, however due to the coincidence of those two now and the price premium of peak electricity, there has been limited ecnomic incentive so far. We (the US) have one heat storing plant and about 2 more exist in the rest of the world but many more are in planning. For unexpected or long term collection outages, you only need to add a natural gas burner to make up heat and you've got full capacity again. This other fuel could theoretically only be needed to supply 2-5% of the energy produced in a full year.
Solar Thermal is occasionally referring to the CSP plants, but usually referring to home based heat collection which may or may not be primarily used for electricity generation. Until just this year, there were no commercially available systems for more than heating water. Now we are seeing offerings which solar thermal advocates, like myself, have been waiting for for years. These systems are optomized for collecting, concentrating and storing the heat at a residence. Once in a tank, it can be dispatched for generation on demand. Since every process is less than 100% efficient, it still has a waste product. The good news is that this is both hot enough and large enough to be put to use onsite. A CSP plant has no use for this waste heat and so must expend energy to actively dump it. If a process wastes 66% of that collected, that roughly satisfies a residential home's heating needs in proportion to its electrical needs. Scaling up such a system would eliminate both energy bills and still have the burner option for critical backup.
My rooftop example above was an attempt to show how much the average roof receives in relation to the home's needs. As you can see, even in January there is more than double what we need. However, as the winter approaches, residential systems become slightly less efficient at making electricity which then causes more waste heat losses... which magically corresponds better to the higher heating needs of the home. It's really a quite elegant system. As you can see, seasonal sun (insolation) is not as bad of an issue as it gets accounted for.
Latitude differences do make a difference, not because of less sun intensity, but because of less hours/day it's available. This only affects the total energy collected and stored - often it is actually more intense. To counter this, one only needs to increase the collected area.
I hope this helps clear up some misunderstandings between us solar THERMAL advocates and those of you yet to join us. :)
Thomas Stacy 6.21.08
Mathew, I applaud your position that educating the public - including elected officials - about wind energy vs. base load capacity - should be a huge priority for the energy industry at large. I disagree, though, that the wind industry should or would take part in clarifying these issues for the common man. This simply is an awkward expectation that flies in the face of basic survival instincts.
Maybe the government of each country should take initiative to "level the propaganda playing field." When momentum as strong as the CO2 nonsense and renewables craze conveniently leaves out important bases of comparison and limitations of the technology, I think a few of the millions of dollars that are offered in tax credits should be diverted to educational media campaigns that point out wind power's redundancy of infrastructure and reduced return on investment in other existing, dispatchable intermediate and peak load generation sources and transmission assets. These are real costs of wind power that the industry would, quite understandably, prefer not to attribute to itself.
Finally, the aesthetic and land use character impacts of wind facilities are enormous when compared to other generation on an annualized kWH production basis. The intrusion/production ratio found on www.savewesternOH.org attempts to capture this basic tenant, albeit in a very simplistic model.
I would love to join forces and exchange further ideas with you.
Cheers, Tom Stacy Save Western OH
Jeffrey Anthony 7.1.08
Mathew -- if you view wind energy as scam, and you base your opinion on every Australian you ask about it, then you are welcome to such an opinion if you base it on the sources you have chosen. And if you chose to base your opinion on the distrorted and intentionally misrepresented number than Len Gould constantly puts out in posts here, then you are entitled to those opinions as well.
And if you subscribe to the theory that capacity factors of 20% to 40% for wind energy projects somehow reflects a design failure or engineering deficiency of wind turbines, then you (like Len) have not taken the time to understand how wind turbines are designed and operated using the variable energy resource that they are designed to capture in an optimal manner. When the wnd blows, they generate electricity and displace electricity from fossil fuel generation, thus reducing harmful emissions into our atmosphere. They are not designed to operate at 100% capacity factor, they are engineered and designed to capture the wind energy resource at a given location and produce electricity based on the wind resource at that location.
One wonders why people don't complain about natural gas peaker plants that operate at 20% capacity factor year after year.... oh yeah, it is a fossil fuel and therefore accepted by the same crowd that has not bothered to learn about how wind turbines operate....
As to the comment from Tom Stacy -- he is typical of the attitude that makes the assumption that the wind industry is trying to replace baseload generation plants, like coal plants, with wind energy. Nothing is further from the truth -- wind power is best viewed as an energy resource that displaces significant emissions when they generate electricity and as an energy resource, they are not counted on as a baseload resource. It is easy for the anti-wind crowd to say the wind industry is trying to promote wind energy as a baseload alternative (when it is not) because then it is easy to show why wind energy cannot replace coal power as a baseload technology.
If you want to discuss wind energy seriously, then you need to learn how the wind industry is positioning and promoting wind energy, not assuming or inventing positions that are easy to criticize when in fact they are not representative of our industry. Len Gould can keep quoting bogus figures in a flawed argument, but I would hope others are more rationale in how they evaluate the benefits and limitations of wind energy as a growing mainstream generating technology in the U.S. and worldwide.