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![]() "Alan Erskine" wrote in message ond.com... On 11/07/2011 10:41 AM, Sylvia Else wrote: The Australian Government has, for reasons that have much to do with politics, and little to do with the environment, decided to throw $Au 10 billion into the bottomless pit that is renewable energy. Lest it all get turned into yet more solar panels and windfarms, I invite all comers to submit their plans for orbital power satellites. At least then we might get some technological advance for our money, even though I doubt we'd actually see any orbital power. Sylvia. How can a SSPS be more efficient than PV on roofs? Also, it will help the environment - I'm studying sustainability at the moment for a future career. Efficiency isn't the key issue. Terrestrial solar has many limits on it's usefulness. From the intermittantcy of day/night, to the storage problem, clouds, rain and especially far from the equator. But the glaring weakness of terrestrial solar, as well as most green forms of energy is they can't ...add...to the baseload grid, only reduce demand here and there. SSP can be directly plugged into a large grid as if it were a conventional power plant. SSP will have many market niches all to itself, so they can charge what they need to if the choice is no electricity. PV isn't the only way of generating electricity. Queensland (an Australian state) is going to get several 250mW solar thermal power plants - small by coal standards, but it helps. ST (Solar Thermal) could also be installed on factory and warehouse roofs for power production (look up SEGS - Solar Electricity Generating System) for about half the cost per kW of PV (solar cells); ST is just not as pretty as PV, especially if the PV is BIPV (Building-Integrated Photo Voltaic). I would think Australia is far more favorable place for terrestrial solar than most other places on Earth. Also, there is TDP (my favourite subject; that I first learned about on one of the sci.space groups in 2003) that can economically turn agriculture and forestry waste into liquid fuels for transport; Are you sure we want to start burning food and forests for energy? What are the longer term implications? Name one power source, of any type, that can provide baseload power 24/7, rain or shine, to any point on Earth? And doesn't require a constant train of expensive oil/gas/uranium/biomass etc etc to pay for year after year??? Once a SSP power satellite goes online, it doesn't need to buy even a single barrel of oil from that day forward. The price of sunlight will never change, never be disrupted by wars or politics. The satellite hardly has any moving parts. And the primary costs of SSP, launch and technology costs should do what in the future? Only go down, especially with technology. Maybe even with launch costs soon, the commercial launch industry seems to be moving ahead pretty fast. gas for heating/electricity production and carbon-rich solids (commonly known as 'bio-char') for soil improvement. A TDP plant can pay for itself in less than three years - with just the sale of oil at $60/bbl - petrol (gasoline to Americans) would cost about $0.80 per litre compared to the current price of $1.30ish. Now, what's the payback period for an SSPS and how many do we need Space Energy inc says it should take about five years for construction, about the same time for a conventional nuclear or coal plant. How do we economically get the power down to the users on Earth? It's the initial costs that are the problem, once operating the ongoing costs are small. What are the environmental risks of getting the power down to the users on Earth? The beam at its strongest point is less than direct sunlight, you can plant crops under a rectenna. Microwaves have been around some 50 years and is a well known technology. Maybe the strongest reason for SSP is the effect it could have on rural third world poverty, disease and hunger. Someone a couple of months ago suggested using laser-powered LV's for payload to LEO - fine, until you try to find the electricity to power those HUGE lasers! Those three questions above have never been answered adequately; please try. Here's a nice 15 minute presentation or sales pitch by Space Energy Inc. http://spaceenergy.com/i/flash/ted_presentation |
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On 14/07/2011 10:23 AM, Jonathan wrote:
Efficiency isn't the key issue. Terrestrial solar has many limits on it's usefulness. From the intermittantcy of day/night, to the storage problem, clouds, rain and especially far from the equator. But the glaring weakness of terrestrial solar, as well as most green forms of energy is they can't ...add...to the baseload grid, only reduce demand here and there. SSP can be directly plugged into a large grid as if it were a conventional power plant. SSP will have many market niches all to itself, so they can charge what they need to if the choice is no electricity. I would think Australia is far more favorable place for terrestrial solar than most other places on Earth. Are you sure we want to start burning food and forests for energy? What are the longer term implications? Look up "Short Rotation Coppice". Look up "Terra Preta" (a soil improvement method). We don't burn either current forests or food itself, just the residues from food and also specially-grown 'forests'. Name one power source, of any type, that can provide baseload power 24/7, rain or shine, to any point on Earth? And doesn't require a constant train of expensive oil/gas/uranium/biomass etc etc to pay for year after year??? There isn't one fossil fuel that does all that right now, not efficiently - in most areas of the world, biomass power production is ideal - it can use crop wastes - Australia could do away with all our fossil fuels four times over just be harnessing our crop residues. Even in the far Northern hemisphere, people use peat for fuel - even powerstations run on the stuff. Then there's geothermal, solar for electricity (both peak-load PV and base-load ST), wind (not my personal favourite - I think wind turbines are just as ugly as high-voltage power stanchons) etc. Remember, most people don't, and won't live in polar or desert areas - either too damn cold or too damn hot for the vast majority of people. That means temperate and tropical areas - lots of biomass there. Once a SSP power satellite goes online, it doesn't need to buy even a single barrel of oil from that day forward. The price of sunlight will never change, never be disrupted by wars or politics. The satellite hardly has any moving parts. And the PV wears out - good for maybe 10-15 years at the outside. Then what? Re-skin the satellites? That's a cost and it will have to be amortised. Nothing is free. We live in a market-driven society that demands a profit be made. And the primary costs of SSP, launch and technology costs should do what in the future? Only go down, especially with technology. Maybe even with launch costs soon, the commercial launch industry seems to be moving ahead pretty fast. Costs of all technologies is going down. That includes Terrestrial solar (PV and ST - solar thermal); biomass is also dropping, faster than the price of fossil-derived energy is increasing. Transport costs will always be higher for an orbital installation. Imagine having to transport all your equipment and materials from one location to another by using an aircraft - that would be far more expensive than using trucks. Labour and assembly will also be more expensive for anything in space. If automated systems are used for assembly, they will also have to be developed. There's another cost. gas for heating/electricity production and carbon-rich solids (commonly known as 'bio-char') for soil improvement. A TDP plant can pay for itself in less than three years - with just the sale of oil at $60/bbl - petrol (gasoline to Americans) would cost about $0.80 per litre compared to the current price of $1.30ish. Now, what's the payback period for an SSPS and how many do we need Space Energy inc says it should take about five years for construction, about the same time for a conventional nuclear or coal plant. Five years from the _start_ of construction! They have no chance of getting that far. Terrestrial PV grew by over 53% last year alone over the previous year and it's growing faster each year with no sign of slowing down. No transport or installation problems for that either. How do we economically get the power down to the users on Earth? It's the initial costs that are the problem, once operating the ongoing costs are small. What are the environmental risks of getting the power down to the users on Earth? The beam at its strongest point is less than direct sunlight, you can plant crops under a rectenna. Microwaves have been around some 50 years and is a well known technology. Maybe the strongest reason for SSP is the effect it could have on rural third world poverty, disease and hunger. Microwaves are also bloody dangerous. Stay out in direct sunlight for any length of time - you'll still get cooked; and that's only for 12ish hours a day - try 24 hours a day. As for what you say about rectennas, you can also use the crops that are _already_ growing there for fuel. Not the crop itself, but the residue (straw etc). In Queensland (north-eastern state of Australia), there are several power stations that use bagasse as fuel - it's the residue left after the sugar is removed from the cane. MSW (Municipal solid Waste - rubbish or trash) is also a source of fuel - a city like Melbourne (4 million) could generate over 13,000 bbls of oil a day from that. Then there's the solid content of sewage to be added to that total - another million tonnes of biomass a day. None of it is currently being used. That's about 10% of Melbourne's total crude oil consumption right there, and we still haven't got to the farms yet. The same technology I've mentioned before, TDP, can help developing and impoverished nations as well. Where do you think they get their current supplies of fuel for electricity generation and transport? It's mostly oil and coal - fossil fuels - and we don't need those. Someone a couple of months ago suggested using laser-powered LV's for payload to LEO - fine, until you try to find the electricity to power those HUGE lasers! Those three questions above have never been answered adequately; please try. Here's a nice 15 minute presentation or sales pitch by Space Energy Inc. http://spaceenergy.com/i/flash/ted_presentation We don't need SSPS even if they were practical, which they are not. We have plenty of resources here on Earth that we are simply not using efficiently or effectively. http://spaceenergy.com is a good-looking website, but it's all 'spin' and no reality. They simply can't compete with Terrestrially produced energy. Solve the problem of transport costs and the problem of assembly and then we can talk about SSPS. |
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On 12/07/2011 11:01 AM, Sylvia Else wrote:
On 12/07/2011 1:35 AM, Alan Erskine wrote: You might want to read this: http://www.cleanenergyfuture.gov.au/ It's mostly propaganda. I agree with government spending on RE, but the tax income from the 'Big 500' will be spent on RE, so industry is paying for RE roll-out. There may be a clever piece of sleight of hand designed to appease the Greens without actually spending money. Most of the money is for "innovative" renewable energy schemes. As long as "innovative" is given a reasonable meaning, the money won't be paid out to construct more of the same solar and wind, and indeed may not be paid out at all in the absence of some real innovation. The latter result may be the government's intent. Sylvia. Propaganda? Rubbish! Yes, the money will be spent on PV and wind systems, as well as other systems. By using the word "innovative" they mean "other than fossil". There is no abscense of innovation in renewable energy, I can assure you. PV grew by over 53% last year alone, compared to the previous year (which had a 40ish % increase on the previous year). Right smack-bang in the middle of a recession. Have a look at what Germany are doing - getting rid of all nuclear power stations before 2020. The shortfall in electricity will be made up with improved efficiency at coal stations and also more RE. There are already power stations in the U.S. and U.K. that run on poplar and willow SRC (Short Rotation Coppice, I recommend looking that up). Not experimental stuff either, but actuall grid-connected power stations. |
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Sunlight on the Earth ranges from 900 hours per year to 2,100 hours
per year, depending on location while energy density ranges from 850 W/ m2 to 1,000 W/m2. Sunlight in space is available for 8,766 hours per year and is at a density of 1,370 W/m2. Low Light: 0.765 MJ/m2/yr High Light: 2.100 MJ/m2/yr Space: 12.009 MJ/m2/yr So, if space based systems are less than 6x the cost of the best terrestrial systems, they're worth doing. Conventional solar collectors cost $1 per peak watt. In a location that has 1,400 hours of sunlight per year that's $0.08 per kWh.. when the sun is shining. When the sun is not shining, there you have a problem. You also have a problem when oil runs out. That's because the manufacturing processes will become far more costly, as well as transport and installation, and you won't have this price any more. Now, using a concentrator to focus light to a small spot, reduces the cost per peak watt, and the cost of energy when the sun is shining. This lets you add systems that store energy when the sun isn't shining, for example by producing hydrogen gas from water, and this with concentrators, can make solar energy useful for all things, including oil, which is what you need when the oil runs out - a source of oil products at less cost than conventional oil - to support your supply chain. http://www.youtube.com/watch?v=dbWNnVsBhOg The cost of water filled lenses operating at 5,000x concentration with $1 per square cm 45% efficient multi-junction cells that cost $0.03 per peak watt. Far less than any conventional solar panel. This produces hydrogen at $100 per metric ton from sunlight and water - equivalent to $4 per barrel. The cost of a gas stabilized concentrator operating at 20,000x concentration at GEO with $1 per square cm 65% efficient multi- junction solar pumped laser that costs $0.007 per peak watt- when beaming IR laser energy back to the terrestrial systems increasing their output 16x - reducing costs to $25 per metric ton - or $1 per barrel. The cost of a radiator stabilized multi-junction power satellite operating at 1,600x ambient levels at 3.5 million from the Sun, beaming energy back to Earth orbiting reformer, operating with the same solar pumped laser system - beaming energy directly to end users at a cost of $1 per metric ton or $0.05 per barrel. Using laser propulsion and laser beams in space radically reduces the cost of space access, which reduces the cost of solar power, which reduces the cost of laser beams in space, which reduces the cost of space access - in what some have called a 'Mook Curve' of decline, similar to a Moore Curve in electronics. Terrestrial http://www.scribd.com/doc/20024019/W...to-Mok-FINAL-1 Space Based http://www.scribd.com/doc/35439593/S...-Satellite-GEO Launcher http://www.scribd.com/doc/45631474/S...rived-Launcher Advanced Systems http://www.youtube.com/watch?v=QvE-bkc0Uxo http://www.youtube.com/watch?v=iWiXDu64c0g http://www.youtube.com/watch?v=XxV2FCUESh0 http://www.youtube.com/watch?v=nzG4PEureFg http://www.youtube.com/watch?v=mzXwctPXT4c http://www.youtube.com/watch?v=LAdj6vpYppA http://www.youtube.com/watch?v=2QAUkt2VPHI |
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Alan Erskine wrote:
Propaganda? Rubbish! Yes, the money will be spent on PV and wind systems, as well as other systems. By using the word "innovative" they mean "other than fossil". No, it means other than fossil or nuclear. So propapanda indeed. There is no abscense of innovation in renewable energy, I can assure you. PV grew by over 53% last year alone, compared to the previous year (which had a 40ish % increase on the previous year). Right smack-bang in the middle of a recession. Following the expontential growth pattern of solar, with a best guess on when it will roll over to an asymptote, suggests around 2030 for the time it replaces nearly all peak load generation. Have a look at what Germany are doing - getting rid of all nuclear power stations before 2020. The shortfall in electricity will be made up with improved efficiency at coal stations and also more RE. Which gives them a decade of being short on electricity. No matter the anti-nuke sentiment by the irrational masses the need is for safer nuke not for less nuke. There are already power stations in the U.S. and U.K. that run on poplar and willow SRC (Short Rotation Coppice, I recommend looking that up). Not experimental stuff either, but actuall grid-connected power stations. |
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On Jul 15, 2:52*pm, Doug Freyburger wrote:
Alan Erskine wrote: Propaganda? *Rubbish! *Yes, the money will be spent on PV and wind systems, as well as other systems. *By using the word "innovative" they mean "other than fossil". No, it means other than fossil or nuclear. *So propapanda indeed. There is no abscense of innovation in renewable energy, I can assure you. *PV grew by over 53% last year alone, compared to the previous year (which had a 40ish % increase on the previous year). *Right smack-bang in the middle of a recession. Following the expontential growth pattern of solar, with a best guess on when it will roll over to an asymptote, suggests around 2030 for the time it replaces nearly all peak load generation. Have a look at what Germany are doing - getting rid of all nuclear power stations before 2020. *The shortfall in electricity will be made up with improved efficiency at coal stations and also more RE. Which gives them a decade of being short on electricity. *No matter the anti-nuke sentiment by the irrational masses the need is for safer nuke not for less nuke. There are already power stations in the U.S. and U.K. that run on poplar and willow SRC (Short Rotation Coppice, I recommend looking that up). Not experimental stuff either, but actuall grid-connected power stations.- Hide quoted text - - Show quoted text - safer nuke will never be absolutely safe nuke. could a nuke plant be built that would survive intact and leak free a complete meltdown? its fine to make them less likely to melt down. but the real design should be a plant that even if it melts down remains intact and leak free |
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On 16/07/2011 4:52 AM, Doug Freyburger wrote:
Alan Erskine wrote: Propaganda? Rubbish! Yes, the money will be spent on PV and wind systems, as well as other systems. By using the word "innovative" they mean "other than fossil". No, it means other than fossil or nuclear. So propapanda indeed. There is no abscense of innovation in renewable energy, I can assure you. PV grew by over 53% last year alone, compared to the previous year (which had a 40ish % increase on the previous year). Right smack-bang in the middle of a recession. Following the expontential growth pattern of solar, with a best guess on when it will roll over to an asymptote, suggests around 2030 for the time it replaces nearly all peak load generation. Have a look at what Germany are doing - getting rid of all nuclear power stations before 2020. The shortfall in electricity will be made up with improved efficiency at coal stations and also more RE. Which gives them a decade of being short on electricity. No matter the anti-nuke sentiment by the irrational masses the need is for safer nuke not for less nuke. There are already power stations in the U.S. and U.K. that run on poplar and willow SRC (Short Rotation Coppice, I recommend looking that up). Not experimental stuff either, but actuall grid-connected power stations. The German nukes aren't closed down until the local capacity has been supplanted by coal/RE. Why do you say propagana? |
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On 16/07/2011 9:39 AM, bob haller wrote:
t - safer nuke will never be absolutely safe nuke. could a nuke plant be built that would survive intact and leak free a complete meltdown? its fine to make them less likely to melt down. but the real design should be a plant that even if it melts down remains intact and leak free Agreed, but that's just not possible. It's like the 'unsinkable' ship, or the car that will never kill its occupants; fine on paper, but just not practical. Making them less failure-prone just makes them more expensive and they're already subject to extremely high subsides. |
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bob haller wrote:
Doug Freyburger wrote: Which gives them a decade of being short on electricity. *No matter the anti-nuke sentiment by the irrational masses the need is for safer nuke not for less nuke. safer nuke will never be absolutely safe nuke. And there's an example of the irrational masses. There's no such thing as an absolutely safe aircraft either, yet I think nothing of flying even though I know more about the mechanics of the plane than most passengers, though less than nearly all pilots. |
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The Voitenko Compressor is a shaped charge that concentrates a
chemical explosion to energy densities needed to set off a fusion reaction - exceeding the Lawson criterion needed for most fusion fuels. Lithium 6 is an isotope of lithium that is deficient in a neutron. It consists of 7.5% of all lithium. Deuterium is an isotope of hydrogen having a spare neutron. One in 6400 hydrogen nuclei are deuterium nuclei. Lithium-6 deuteride - is a form of lithium hydride - a powder - that has these two types of nuclei. When Lithium-6 deuteride is compressed and heated to over 100 million degrees Kelvin, the two nuclei fuse and form two Helium-4 nuclei releasing 576 trillion joules per kg. A tiny fusion reaction started by a small chemical compressor may be expanded to any size limited only by the availability of suitable fuel. Both lithium-6 and deuterium may be extracted from seawater by simple processes at a cost of $20 per kg. This is equivalent to the heat of burning 4,721 barrels of crude oil for $1. Micro-electro-mechanical systems may be produced that operate as Voitenko compressors costing only fractions of a penny per device in quantity. A 1 micro-gram fuel element releases 1.58 mega-joules. Detonated in a tank of working fluid, like water, every 21.8 seconds, this produces a tank of steam that produces energy at a steady rate of 26,400 Watts thermal. Run through a steam turbine at an efficiency of 38% - this produces 10,000 Watts electrical - continuously. A system like this in quantity would cost $500 and would contain 29 grams of lithium deuteride fuel, which would be sufficient at this rate to allow the turbine to operate continuously for 20 years. The cost of the fuel would be $0.60 of the total price. These would be suitable for powering and heating homes, offices, factories and vehicles. Producing these units at a rate of 75 million per year (about equal to current world automobile production) and with a 20 year life span, 1.5 billion units could become operational over this period. At 10,000 watts each this represents the present energy consumption of the entire world. A supply chain to produce 300 million units per year (possible as a crash measure, similar to the production of weapons in World War 2) and with the same 20 year life span - the world's existing power infrastructure would be replaced in five years and the world would have a global capacity of 6.0 billion units - approximately 4x the present power production on the planet. When applied usefully to industry, this surplus energy would raise living standards throughout the world. For this reason I am putting in my Bergius coal-to-liquid systems a means to extract deuterium from the 2,500 tonne per day hydrogen stream per unit. 14 units x 2,500 tons per day / 6,400 x 2 amu/atom = 10.9 tonnes per day of deuterium. Another process extracts 436 tonnes of lithium from the ocean each day, and then separates out 32.7 tonnes per day of Lithium 6. The lithium and deuterium are combined to produce 43.6 tonnes per day of fuel containing 25.11e+18 Joules of energy. If this were all released in power plants this would generate a total power level of 290.7 trillion watts - about 19x what the world consumes per day. While large by 20th century standards, this is just the 'proof of concept' of the system. Hundreds of ships built each year need thousands of tons per trip, which require expansion - as the means for production is built up. Capturing even a small portion of the world's energy markets, allows this to be paid for. There are 200 billion tons of lithium in the world's oceans. Only a small fraction is used before opening resources off world. |
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