![]() |
|
|
Thread Tools | Display Modes |
|
#1
|
|||
|
|||
![]()
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. |
#2
|
|||
|
|||
![]()
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. 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). 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; 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? How do we economically get the power down to the users on Earth? What are the environmental risks of getting the power down to the users on Earth? 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. |
#3
|
|||
|
|||
![]()
On 11/07/2011 5:33 PM, Alan Erskine wrote:
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. Well, it does have the advantage of not being subject to the vagaries of the weather, and (if not in LEO) is in sunlight for most of the time - it has no significant night time. The economics of surface PV are complicated by the need to include the cost of backup generation capacity (the cost is usually ignored by proponents). 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). Solar thermal has some advantage in terms of being able to deliver power overnight, but still has the limitation that weather can render it powerless. 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; 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? The payback period depends, among other things, on the price that the power can be sold for. I rather doubt that the price will ever be high enough to allow payback. I've only made the suggestion on the basis that if the money is going to be wasted anyway, it might as well be wasted in a way that might have some spin-off benefit. How do we economically get the power down to the users on Earth? What are the environmental risks of getting the power down to the users on Earth? 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. I think the idea was completely debunked anyway, on the grounds that the proposed numbers were totally wrong. Sylvia. |
#4
|
|||
|
|||
![]()
On 11/07/2011 6:00 PM, Sylvia Else wrote:
On 11/07/2011 5:33 PM, Alan Erskine wrote: On 11/07/2011 10:41 AM, Sylvia Else wrote: 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. Well, it does have the advantage of not being subject to the vagaries of the weather, and (if not in LEO) is in sunlight for most of the time - it has no significant night time. The economics of surface PV are complicated by the need to include the cost of backup generation capacity (the cost is usually ignored by proponents). It _is_ subject to the vagaries of the weather - microwaves are absorbed by clouds. Sure, pick a site for the rectenna where there are no clouds - the same areas where there are no people. Then you have to take into account the huge line losses (look up "voltage drop") on the power lines. 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). Solar thermal has some advantage in terms of being able to deliver power overnight, but still has the limitation that weather can render it powerless. No. When there's no Sun available, the alternative energy source comes into play - usually natural gas at the moment, but wood gas or another biomass-derived fuel is used to heat the working fluid - that's why it works when there's no Sun. That's the main reason for it being less expensive than PV. 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; 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? The payback period depends, among other things, on the price that the power can be sold for. I rather doubt that the price will ever be high enough to allow payback. I've only made the suggestion on the basis that if the money is going to be wasted anyway, it might as well be wasted in a way that might have some spin-off benefit. How do we economically get the power down to the users on Earth? What are the environmental risks of getting the power down to the users on Earth? 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. I think the idea was completely debunked anyway, on the grounds that the proposed numbers were totally wrong. Sylvia. The money isn't going to be wasted; half is going to compensate for increased power bills from the big power companies that are the main source of carbon pollution. The other half is to be invested in renewable energy. This will also encourage the big polluters to improve things for their existing systems and eventually replace them with RE (Renewable Energy) systems. I remind you that we are not the first country to go this route - Germany announced in May that they are eliminating nuclear power altogether by 2020 - nine years away. The way they are doing that is to increase the efficiency of their coal-fired power plants (technology that can be used here in Australia) and also for more RE. |
#5
|
|||
|
|||
![]()
On 11/07/2011 11:26 PM, Alan Erskine wrote:
The other half is to be invested in renewable energy. With a carbon price capturing the external cost of carbon emissions, renewable energy schemes should not require public funds other than for research and, if it gets that far, proof of concept, neither of which requires the expenditure of $billions. Hot rocks may make it on its own given the carbon price, but any money spent on capitalising solar and wind is, as I said, wasted. Sylvia. |
#6
|
|||
|
|||
![]()
On 11/07/2011 11:55 PM, Sylvia Else wrote:
On 11/07/2011 11:26 PM, Alan Erskine wrote: The other half is to be invested in renewable energy. With a carbon price capturing the external cost of carbon emissions, renewable energy schemes should not require public funds other than for research and, if it gets that far, proof of concept, neither of which requires the expenditure of $billions. Hot rocks may make it on its own given the carbon price, but any money spent on capitalising solar and wind is, as I said, wasted. Sylvia. You might want to read this: http://www.cleanenergyfuture.gov.au/ 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. |
#7
|
|||
|
|||
![]() "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 |
#8
|
|||
|
|||
![]()
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. |
#9
|
|||
|
|||
![]()
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 |
#10
|
|||
|
|||
![]()
On Jul 10, 5:41*pm, 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. First, super-insulated houses for all then everything else. Then more efficient lighting, frigs, etc. Then a better grid with storage such as compressed air or molten sodium to drive generation when renewables are set, not blowing, or not sloshing. Don't forget geothermal by way of injection into dry wells that might be possible as well. Orbital power looks like an attractive target or perhaps a likely target for orbital crap left over from creation given it's going to up forever so to speak. Then again it might work to have space power....................Trig |
Thread Tools | |
Display Modes | |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
..Space Energy Inc plans to launch prototype Space Solar Power Satellite | Jonathan | History | 10 | December 22nd 09 04:17 AM |
Europe, Russia discuss 'orbital shipyard' plans | [email protected] | Policy | 50 | May 23rd 09 11:02 PM |
PopSci feature on Robert Bigelow and "CSS Skywalker" orbital resort plans | Neil Halelamien | Policy | 4 | February 17th 05 09:23 AM |
Rutan describes plans for orbital spacecraft | Neil Halelamien | Policy | 14 | October 11th 04 01:45 AM |
calculations of orbital decay for the Nebular Dust Cloud theory why has no astronomer or physicist calculated | Archimedes Plutonium | Astronomy Misc | 6 | January 13th 04 07:42 PM |