There is an illustration called Figure 0.1 in the German Soace Agency written report Energy [r]evolution. That report claims that the U.S. can, "with off-the-shelf technology, cut CO2 emissions from current levels by 23 percent by 2020 and 85 percent by 2050". Now I regard the goal of decreasing CO2 emissions by 85% in 2050 as whole laudable. Laudable, but not easy to achieve, and very very difficult to achieve without some breakthroughs in nuclear technology. I must also add that none of the breakthroughs seem to represent insurmountable challenges. And the reward for a commitment to seek the breakthroughs is a sustainable future of abundant low cost electrical power.
What is interesting about figure 0.1 is that it shows that by 2050 almost all energy will come from two sources "Efficiency and Renewables". It would appear from Figure 4.11 that by 2050 energy [r]evolution anticipates that energy demand will be at least cut in half by "efficiency." I will defer discussing efficiency until another post and concentrate on renewables. I have already explored two more reliable renewable energy sources - biomass and geothermal - and pointed to significant problems with both.
Biomass and geothermal might be considered minor renewables, while solar and wind are the main show. One practice of energy [r]evolution that creates confusion is the choice to describe energy sources in terms of installed capacity. This causes few problems when coal or nuclear because installed capacity signals an availability almost all of the time. Natural gas capacity is not available all of the time, simply because there is not enough gas to keep the gas generators running all of the time. Even if there were producing base load electricity with natural gas is very expensive. Still natural gas has the potential to produce electricity on demand. Unfortunately several renewable sources lack the ability to produce energy on demand. These include wind. photovoltaics, and solar thermal electrical generation sources. This limitation of common renewables is a significant handicap. The inability of major renewables options to produce energy on demand requires serious attention. To believe that the handicaps of intermittent electrical generating sources can be easily overcome and therefore they can be counted on as stable base energy sources for the future is simply unrealistic.
We will start with wind. The [r]evolutionaries expect that between now and 2020 there will be a great boom in wind with installed wind capacity increasing from 31 gWs in 2010 too 258 gWs in 2020, after that the pace of wind expansion is expected to level off with another 100 gWs added by 2030 and then a little more than 40 gWs more by 2050. We have remarkably little information about this. For example, we do not know how much of the wind capacity will be off shore and how much will be land based. Again we do not know where the land based windmills will be located. Lacking such information it would be impossible to come up with even approximate answers to important questions such as how much power could installed wind capacity be expected to produce at any given time. Jason at Pronuclear Democrat has pointed out that the term "capacity factor" is never used in the Energy [r]evolution discussion, so we don't have a measure of how useful the wind generated power would be. And indeed in order to be very useful wind generated electricity would have to be available when consumers want it.
Consumers generally want electricity during their 16 waking hours hours, while electrical demand drops during their sleeping hours for some mysterious reason. Curiously more wind generated electricity is produced during the night than during the day, and over much of the United States less windmills produce less power during the summer than during the winter. Wind power output can drop dramatically on very hot summer days, and ironically during very cold periods during the winter. Even wind advocates acknowledge that wind power is not dispatchable. It cannot be delivered on demand. Rather than focus on the weakness of wind, they insist on focusing on the cost of wind generated electricity when it is produced. This is unfortunate because the wind may be blowing between steadily between 11:00 PM and 5:00 AM delivering unwanted power at 5 cents a kWh, but not delivering power between 11:00 AM and 5:00 PM when gas powered generators produce power at 11 cents a kWh.
Consumers generally want electricity during their 16 waking hours hours, while electrical demand drops during their sleeping hours for some mysterious reason. Curiously more wind generated electricity is produced during the night than during the day, and over much of the United States less windmills produce less power during the summer than during the winter. Wind power output can drop dramatically on very hot summer days, and ironically during very cold periods during the winter. Even wind advocates acknowledge that wind power is not dispatchable. It cannot be delivered on demand. Rather than focus on the weakness of wind, they insist on focusing on the cost of wind generated electricity when it is produced. This is unfortunate because the wind may be blowing between steadily between 11:00 PM and 5:00 AM delivering unwanted power at 5 cents a kWh, but not delivering power between 11:00 AM and 5:00 PM when gas powered generators produce power at 11 cents a kWh.
Given the lack of dispatchablity with wind, some wind advocates suggest ann adjustment in human behavior as accodomadations to the limitations of wind. For example staying up past midnight to do laundry, running air conditioners at night to chill houses far below a comfortable temperature and then shutting off the air conditioner during the daytime, trusting that the very cold house will not heat up too fast.
In an earlier part of this study I noted that the energy [r]evolution plan projected a growth in natural gas generation capacity at the same time it projected a growth in wind capacity. This was not an accident. Wind requires dispatachable back up - load leveling, and reserve generation capacity. Who are you going to call on for that. Natural gas of course. Hence the tail wags the dog. Natural gas becomes clean energy, because no renewable energy form is going to supply sufficient backup for wind in 2020, and so fictions are introduced about the potential for efficiency and the "cleaness" of natural gas.
Nuclear power must be quickly eliminated from the energy [r]evolution schemes because nuclear power competes directly with wind overnight. And the old reactors, competing with wind, pump out electricity at a lower cost than wind does.
In order for wind to truly replace nuclear power surplus electricity from wind generators would have to be stored and dispatched A couple of thousand wind generators would have to be hooked up to batteries, even more if energy was to be stored in pumped storage or compressed air facilities. The whole windmills storage system would end up costing more than new nuclear power plants would.
Energy [r]evolution ignores the question of how much its wind component will cost. Indeed the entire issues of renewables cost is remarkably hedged not just by the Energy [r]evolution report, but in the entire realm of discourse about renewables, although we are repeatedly assures how low cost it renewables are, and how the cost of renewables have dropped during the time it has taken you to read this post. Indeed if I don't stop writing soon the price of wind generators may drop to zero before I finish.
In the real world the price of wind generators has risen steadily since 2002, and it is hard to get at the price of wind generators. My most recent investigation suggested a price of about $2500 per kW installed during mid 2008, but my sampling technique was not scientific. Recently Jorge Barrera of MIT stated:
If we note that the price of wind installations has risen from $1000 per kW to $3000 per kW between 2002 and 2008, we have to acknowledge that there is an ongoing inflationary tend in the wind industry. A similar tend in the nuclear power industry has been noted, and is often mentioned by renewables advocates, while the inflation of renewables costs is seldom noted.
So how much would building 225 GWs or so of wind generating capacity by 2020 cost? If the price of wind generators does not rise between 2020, we are looking at $690 billion. I don't even want to think what it cost if the present inflationary trend were to continue. If the cost averaged twice the 2008 cost we are looking at 1.4 trillion dollars. That for a part time, non-dispatchable power source. Making wind more reliable could easily triple our cost.
Photovoltaics
Photovoltaics advocates frequently tell us how in a few short years the cost of PVs will be so cheap that it would be too cheap to meter. I am sorry the devil made me say that. There has been a steady drum beat for lower solar costs for some time, in fact for some time before I was born since 1942, Well I need to get myself under control. So lets look at this abstract dated the Journal of Materials Science, April 1983.
Many will argue that they are recuperating the cost of R&D, others that material cost have gone up, or that it's a sellers market, simply put to much demand. The fact is that current prices are about 3million a megawatts install that means that a 2MW turbine cost about 6M to put up. Now knowing about manufacturing and talking to the suppliers of equipments one can estimate that the real cost is about 1M/MW install.The practicality of any scheme to deploy massive wind wind resources depends on the price of wind installations. Thus T. Boone Pickens announced last year that he planned to install 667 1.65 MW wind generators at an anticipated cost of around two billion dollars in two thousand eleven. How seriously should we take Pickens price quote? I would not think it has no value, but i would not make a bet on the price based on the Pickens quote either.
. . . the 3M/MW does not include a warranty, that is extra and maintenance cost are a problem with this project so far, it is hard to find anyone in the business not worried about the raising maintenance cost of such systems.
If we note that the price of wind installations has risen from $1000 per kW to $3000 per kW between 2002 and 2008, we have to acknowledge that there is an ongoing inflationary tend in the wind industry. A similar tend in the nuclear power industry has been noted, and is often mentioned by renewables advocates, while the inflation of renewables costs is seldom noted.
So how much would building 225 GWs or so of wind generating capacity by 2020 cost? If the price of wind generators does not rise between 2020, we are looking at $690 billion. I don't even want to think what it cost if the present inflationary trend were to continue. If the cost averaged twice the 2008 cost we are looking at 1.4 trillion dollars. That for a part time, non-dispatchable power source. Making wind more reliable could easily triple our cost.
Photovoltaics
Photovoltaics advocates frequently tell us how in a few short years the cost of PVs will be so cheap that it would be too cheap to meter. I am sorry the devil made me say that. There has been a steady drum beat for lower solar costs for some time, in fact for some time before I was born since 1942, Well I need to get myself under control. So lets look at this abstract dated the Journal of Materials Science, April 1983.
A study has been made of the possibility of producing ceramic substrates for low-cost solar cells by means of the simple technology of moulding by dry-pressing. . . . Even if this methodology has been applied on a laboratory scale, it is quite easy to automate it for industrial scale production.Solar advocates keep telling us that the prices of solar voltaic modules are dropping like rocks. Joel Conkling and Michael Rogol claim
The decoupling of solar power prices from their underlying costs hides the low and rapidly falling cost structure of solar power. Today, the »true cost« of solar power is under 25¢ per kWh in most locations and is likely to reach 10¢ to 15¢ per kWh by 2010. This includes all costs of manufacturing and installing solar power systems from pre-silicon (i.e. TCS) to connected-installations without incentives or tax benefits.
Already, solar is at a cost level that makes it competitive with residential grid prices in the OECD's highest-priced markets. It is estimated that the cost of solar power is below the price of residential grid electricity for 5 to 10 percent of OECD consumption (200 to 400 TWh). This equates to 150 to 300 GW of solar power, compared to only 2.7 GW of solar cell/module production in 2006.
Over the next three years, it is expected that the typical fully-loaded cost of solar power will decrease at least 30 percent from $3.60 per W in 2006 to $2.50 per W. In consequence, by 2010, the cost of solar will be below the price of grid electricity for at least 50 percent of OECD residential demand, equivalent to around 1,500 GW of solar power. This is much larger than the 15 GW of cell/module production PHOTON Consulting anticipates for 2010
Solarbuzz, which is a source of information for people who are in the PV business, is perhaps more realistic.
Solar Electricity Prices are today, around 30 cents/kWh, which is 2-5 times average Residential electricity tariffs.
There is no doubt that the cost of installed solar PVs have dropped some over the last decade, but the Christian Science Monitor recently told us that is not all there is to the story:
Heat is an especially difficult problem for PV, and one approach to making PV's more efficient is to use water to cool them. It has been suggested that PVs and solar hot water heating can be combined. This is no doubt can be done, but is it cost effective? In localities like Oak Ridge clouds would not only decrease power production, but hot water production as well. According to Solarbuzz a 1kWp System will produce approximately:
Finally it should be noted that PVs like windmills must be connected to storage systems, in order to dispatch electricity when it is demanded by customers. It would appear that the same consideration we encounter with wind storage apply to PV storage as well, and as a consequence PVs will
There is little doubt that PV with storage today and at least for the near term future will be far more expensive than nuclear power by kW of 24 hour a day generating capacity.
Solar Thermal
One of the technical problems with PV power is that sunlight heats. PV cells loose their effency as their internal temperature rises. Thus an alternative approach would be to capture solar energy via heat rather than producing electricity directly from sunlight. This can be done by heating water with sunlight. Solar hot water heaters provide useful electrical savings in sunny areas, and would be extremely worthwhile investments in places like southern California. A second use of heat from sunshine would be for space heating. Again this would be most useful in sunny areas like California, and would be far less worthwhile in places like Oak Ridge, Tennessee.
Yet another use of solar heat would be to heat some liquid, water, oil, or liquid salt, until the boiling point of water is reached. Water would be heated above the boiling point, either by direct heating, or by passing through a heat exchange with another solar heated fluid. The steam is then used to drive turbines. An alternative system would be to heat a gas that would be intern provide working power for a Sterling Engine.
Unsubsidized, solar energy still can't compete in most energy markets. The pay-back period is too long. Reports of more efficient solar panels are helping reduce costs but about half of the expense for solar is still borne by taxpayers.And of course the problem of the solar PV story is that PVs only provide on average about 20% of their name tag power in always sunny Southern California, on their best days. If you are looking at solar performance in other parts of the country, on bad days, it gets much worse. While you do get some power from PVs on cloudy days, You still need more PVs or other power systems to make things work. Now how much electricity do you need? Well the average American household uses 6000 kWh of electricity a year, but in addition it uses enough natural gas to equal another 12,000 kWh of electrical energy. If the use of natural gas is to be replaced in the American Home, it will almost certainly be replaced by electricity, although non-electrical solar technologies could play a role. In particular solar technology could play a significant role in water and space heating. And in addition there are more efficient electrical options - air source and ground source heat pumps. Let us assume that we are going to make our home more energy efficient, and use solar heat for water and space heating. Well not entirely because we may need to heat water and our house at night. Lets say that our post carbon energy efficient house cuts its needs 12,000 kWh of electricity a year. This represents an efficiency gain of one third of the former total energy use. We are going to average nearly 33 kWh per day. This means that on average if we assume Southern California sunlight standards, we would need solar PV modules with the name plate capacity of 7.3 kWs to provide all of our electricity. In addition we will need to provide space somewhere for our solar hot water heater and possibly our solar space heating unit. Clouds decrease PV efficiency. Were we to move from Southern California to my former home town of Oak Ridge in East Tennessee, however, we would find that ourselves confronted with 158 cloudy days a year, and another 97 partially cloudy days. PV can be expected to provide less power in the winter than in the summer. However, heat on summer sunlight heats raises the temperature of solar cells, decreasing their efficiency. Dust on the surface of solar cells decrease their efficiency. Tracking the sun would increase solar efficiency, but adding a solar tracking system increases costs. Electrical inverters used to transform DC solar electricity to AC, decrease PV efficiency. Thus when PV advocates tell us that a certain PV price will make PVs competitive we have to ask if the calculation includes all of those factors that decreases PV efficiency.
Some advocates want Congress to commit to $420 billion in solar subsidies – nearly the same cost to build the Interstate Highway System. This might allow solar to reach price parity with other major energy sources within a decade.
Heat is an especially difficult problem for PV, and one approach to making PV's more efficient is to use water to cool them. It has been suggested that PVs and solar hot water heating can be combined. This is no doubt can be done, but is it cost effective? In localities like Oak Ridge clouds would not only decrease power production, but hot water production as well. According to Solarbuzz a 1kWp System will produce approximately:
· 1800 kWh/year in Southern CaliforniaWe need to know a great deal more about PV inefficiencies before we can judge when PVs are likely to reach the point of economic viability. We do know however that the PV cheerleaders know far to little to offer us any insight.
· 850 kWh/year in Northern Germany
Finally it should be noted that PVs like windmills must be connected to storage systems, in order to dispatch electricity when it is demanded by customers. It would appear that the same consideration we encounter with wind storage apply to PV storage as well, and as a consequence PVs will
There is little doubt that PV with storage today and at least for the near term future will be far more expensive than nuclear power by kW of 24 hour a day generating capacity.
Solar Thermal
One of the technical problems with PV power is that sunlight heats. PV cells loose their effency as their internal temperature rises. Thus an alternative approach would be to capture solar energy via heat rather than producing electricity directly from sunlight. This can be done by heating water with sunlight. Solar hot water heaters provide useful electrical savings in sunny areas, and would be extremely worthwhile investments in places like southern California. A second use of heat from sunshine would be for space heating. Again this would be most useful in sunny areas like California, and would be far less worthwhile in places like Oak Ridge, Tennessee.
Yet another use of solar heat would be to heat some liquid, water, oil, or liquid salt, until the boiling point of water is reached. Water would be heated above the boiling point, either by direct heating, or by passing through a heat exchange with another solar heated fluid. The steam is then used to drive turbines. An alternative system would be to heat a gas that would be intern provide working power for a Sterling Engine.
At this point I stopped working on the essay. Barry Brooks had just posted Solar Fraud on Brave New Climate. Solar Fraud is a review of the book ‘The Solar Fraud: Why Solar Energy Won’t Run the World“ by Howard Hayden, This was the first of several posts in which Brwve New Climate covered solar issues, and which made further analysis from me redundant. These pos includedPeter Lang's Solar Power Realities, and Solar Realities Addendum, Ted Trainer's Solar thermal questions, and a recent case study by Peter Morcombe, Solar Power in Florida. A separate post by Tom Blees, titled Germany - Crunched by the Numbers that focused on Solar power performance in Germany. Taken together these posts bring a powerful case against the Greenpeace position on Solar Thermal energy. So rather than complete my original plan review plan I will simply refer my readers to the Brave New Climate posts and their discussions which run to hundreds of comments.
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