- He set the flat array at an angle of 45 degrees. Is that the optimum angle for solar panels at his latitude?
- as mentioned elsewhere, more panels in the tree array.
- The photos show both arrays being partly shaded by trees in the yard. Since the arrays aren't at exactly the same position, the amount of shade can be different. The tree array is at an advantage: more distance between the panels means that it's less likely that more than one panel is shaded by a tree branch.
Still, it's an interesting result that raises a few questions: - in current solar panels, the wafers are connected to their beighbors to minimise the amount of wiring. But this means that whole panel drops its output below the threshold if one row of wafers is shaded by a tree branch. Maybe we'd get more energy out of an array if we connected distant wafers in series instead, so a tree branch shadow is less likely to drop the output of a series of wafers below the threshold.
- is it possible to increase the output of an array by putting parts of it at different horizontal or vertical angles?
No, GP is correct, the new port will accept current plugs. They've sawed the port in half and put it at the surface of the device, so there's plenty of room for old cylindrical plugs.
This is a recipe for disaster. TRS connectors are very susceptible to hum: when you touch a live TRS connector, your skin conducts enough to make a circuit between the connector poles. With the connector exposed on the surface of the device, you'd get loud noises every time you accidentally touched the connector. For this to work, the connector has to be covered, negating at least part of the thickness reduction they're seeking.
Also the magnet they propose for keeping the plug in place is going to have to be pretty strong to withstand normal jostling etc. of the device in a pocket. Unlike the Magsafe power connector, this jack need to be kept in place without interruptions. The tiniest shift between the plug and socket results in crackles and other loud noises.
TFA isn't very clear, but the diagrams help. Apple wants to put the socket (receptacle, female*) at the surface of the device. Apple's new headphone plug (male part, found at the end of the headphone cable*) would be flush with the surface. Old headphone plugs also fit, but they would not be flush. Since the plug is only supported on one side, a magnet is needed to keep it from falling out. To compensate for the ugliness of having the connector exposed, Apple proposes to provide their headphone plugs with a cosmetic cover.
Interstellar travel is going to require quantum leaps in technology, not just incremental improvements. It makes perfect sense to start funding research to find those quantum leaps, regardless of our current space program.
We already have a fuel tax, in fact more than 50% of the fuel prices is taxes. But that's not what this scheme is about. There are two goals: 1. to combat congestion, by setting a high price for road sections and times where congestion occurs.
2. to replace the current car sales tax (BPM) and ownership tax. BPM and ownership taxes are used to promote clean, efficient vehicles: cars with the lowest CO2 emissions enjoy lower taxes. BPM goes against European regulations so it will have to be replaced eventually. The ownership tax currently discriminates against people who don't drive much: the tax tariff is independent of your kilometrage, so you pay taxes even if you don't use the car.
I used to have to ask someone where the nearest this or that could be found.
To me (and many others), the need to ask for directions (and then interpret ambiguous or incorrect directions), or laboriously plot a route and write down directions that are readable while driving WAS a problem.
GPS has taken the stress out of driving in unfamiliar areas, and that's a good thing. On my last vacation trip without GPS, I spent hours divining where to go from incomplete and/or incorrect directions, hours that contributed nothing in the way of enjoyment or adventure. Just frustration.
In my opinion, GPS/GNSS has not solved *any* issues in the civilian world. It has (over)simplified and depersonalized navigation
Are you enjoying your ivory tower? I can't believe you're advocating the idea that navigation should be difficult.
In that case a revisit is worthwhile. Much has changed in the past few years, with new exhibition spaces becoming available, the Colossus and bombe, and all the other stuff you mention. Try and plan your visit on a day that the National Museum of Computing (on the same grounds, but operated independently with rather limited opening hours) is also open.
IMO the big news is that the printed parts are strong enough to do this. The printing processes I've seen so far result in parts that are too brittle to serve as anything except decoration or as mould masters.
It used to be that solar panels were by far the most expensive part of an installation. At the moment, for an installation that can supply 1350 kWh/year, the panels cost E4500, the inverter is E1200, labor is in the region of E1000 as well I suspect. So the panels are still 66% of the total cost. Two years ago, the panels would have cost E8500, or more than 80% of the total cost. When the cost per Watt reaches E1, the panels will be 50% of the installation cost. At that point savings in the cost of inverters and installation will become more critical than they are now.
The difference is that the US has chosen not to pursue the Shuttle program, so that the money can be spent on never ending social programs.
Yes, social programs like 2 simultaneous wars halfway across the globe, and paying interest on the national debt.
There ware good technical reasons to end the Shuttle program. The Shuttle configuration is flawed, and no amount of updated components is going to change that. It was time for a clean sheet.
The US is on its way to being able to provide Saturn V-class launches again. Only this time it's a private company instead of NASA. That's not a bad thing.
Missions that are too heavy to fit within the load envelope of Dragon don't necessarily need a Shuttle. ISS modules and other heavy infrastructure can be lofted on an unmanned Falcon 9 (or Falcon 9 Heavy, if you really need to shift some weight). Between Dragon, ATV and HTV the need to bring equipment racks to the ISS is covered. Satellite repair has been done 10 times, 5 of which were to Hubble. The cost of these missions was so high that it's generally cheaper to launch a new satellite than to send up a Shuttle to repair it. Similarly, satellite retrievals have been rare. Both functions could be useful if a vehicle was available that can do this at 10% of the cost of a Shuttle mission. That should be the goal, not retaining the Shuttle.
Solar Cells, and Lightning Rods seem to be the only methods I can think of that produce electricity without the use a turbine/generator combo but neither are viable for wide spread use.
Is 17 GW 'wide-spread' enough for you? Because that's the amount of solar cell generating capacity installed in Germany as of 2010. Solar cell prices have been dropping like a brick, and right now the payback time of a small-scale solar installation (~20 years) is shorter than the projected lifetime (at least 25 years).
The 'aside' you mention is actually the main point. Even the most efficient power plants top out at 60% efficiency. Assuming your house is heated with gas, not electricity, this means that the light bulb is slightly over half as efficient as your gas furnace. For a recent (less than 15 yo) gas furnace over here (.nl) efficiency is in the 95%+ range, thanks to government incentives towards more efficient systems. Dunno about the US situation.
Also, heat and light needs don't overlap: you'll be running those same lights in the summer, when your AC will be running overtime to pump out the excess heat from the damn bulbs.
Finally, the effect of light bulbs on heating is negligible. My central heating is rated at 25 kW, and I have 13 light fixtures. If I installed 100W incandescent lights everywhere I would generate ~1300W in heat, or 5% of the peak capacity I need.
sonic booms indicating Atlantis has gone subsonic.
Do they? AIU, the sonic boom is generated as long as the aircraft is supersonic. So the booms recorded on the video merely indicate that Atlantis was supersonic at some point close enough to the camera. The point where speed drops below Mach 1 cannot be determined from that.
The video shot by Castillo highlights a problem that occurs when you shoot video with the sky as its background, or in the dark: you have no reference frame for the movement of the camera, so it becomes difficult to judge what you're seeing. Case in point: in this video, the camera zooms in and then pans along the flightpath, making it look like the Shuttle changes speed.
The same problem happens in e.g. video of an airplane doing aerobatics: you can't separate the movement of the airplane from the movement of the camera.
I used to play flight simulator games, and these showed that there's a simple solution to this problem: show azimuth and elevation markings along the edges of the screen; this makes it easy to see that the camera is moving. With today's accelerometers, it should be possible to add this functionality to a camera...
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- He set the flat array at an angle of 45 degrees. Is that the optimum angle for solar panels at his latitude?
- as mentioned elsewhere, more panels in the tree array.
- The photos show both arrays being partly shaded by trees in the yard. Since the arrays aren't at exactly the same position, the amount of shade can be different. The tree array is at an advantage: more distance between the panels means that it's less likely that more than one panel is shaded by a tree branch.
Still, it's an interesting result that raises a few questions:
- in current solar panels, the wafers are connected to their beighbors to minimise the amount of wiring. But this means that whole panel drops its output below the threshold if one row of wafers is shaded by a tree branch. Maybe we'd get more energy out of an array if we connected distant wafers in series instead, so a tree branch shadow is less likely to drop the output of a series of wafers below the threshold.
- is it possible to increase the output of an array by putting parts of it at different horizontal or vertical angles?
No, since the connector is not encased in a socket but held on by a magnet, very little leverage can be applied to the connector.
No, GP is correct, the new port will accept current plugs. They've sawed the port in half and put it at the surface of the device, so there's plenty of room for old cylindrical plugs.
This is a recipe for disaster. TRS connectors are very susceptible to hum: when you touch a live TRS connector, your skin conducts enough to make a circuit between the connector poles.
With the connector exposed on the surface of the device, you'd get loud noises every time you accidentally touched the connector. For this to work, the connector has to be covered, negating at least part of the thickness reduction they're seeking.
Also the magnet they propose for keeping the plug in place is going to have to be pretty strong to withstand normal jostling etc. of the device in a pocket. Unlike the Magsafe power connector, this jack need to be kept in place without interruptions. The tiniest shift between the plug and socket results in crackles and other loud noises.
TFA isn't very clear, but the diagrams help. Apple wants to put the socket (receptacle, female*) at the surface of the device. Apple's new headphone plug (male part, found at the end of the headphone cable*) would be flush with the surface. Old headphone plugs also fit, but they would not be flush. Since the plug is only supported on one side, a magnet is needed to keep it from falling out.
To compensate for the ugliness of having the connector exposed, Apple proposes to provide their headphone plugs with a cosmetic cover.
*just making sure there's no confusion
Interstellar travel is going to require quantum leaps in technology, not just incremental improvements. It makes perfect sense to start funding research to find those quantum leaps, regardless of our current space program.
Helium isn't exactly abundant. Is it wise to vent such huge amounts of it into space just for tourism?
We already have a fuel tax, in fact more than 50% of the fuel prices is taxes. But that's not what this scheme is about.
There are two goals:
1. to combat congestion, by setting a high price for road sections and times where congestion occurs.
2. to replace the current car sales tax (BPM) and ownership tax. BPM and ownership taxes are used to promote clean, efficient vehicles: cars with the lowest CO2 emissions enjoy lower taxes.
BPM goes against European regulations so it will have to be replaced eventually. The ownership tax currently discriminates against people who don't drive much: the tax tariff is independent of your kilometrage, so you pay taxes even if you don't use the car.
You contradict yourself.
I used to have to ask someone where the nearest this or that could be found.
To me (and many others), the need to ask for directions (and then interpret ambiguous or incorrect directions), or laboriously plot a route and write down directions that are readable while driving WAS a problem.
GPS has taken the stress out of driving in unfamiliar areas, and that's a good thing. On my last vacation trip without GPS, I spent hours divining where to go from incomplete and/or incorrect directions, hours that contributed nothing in the way of enjoyment or adventure. Just frustration.
In my opinion, GPS/GNSS has not solved *any* issues in the civilian world. It has (over)simplified and depersonalized navigation
Are you enjoying your ivory tower? I can't believe you're advocating the idea that navigation should be difficult.
In that case a revisit is worthwhile. Much has changed in the past few years, with new exhibition spaces becoming available, the Colossus and bombe, and all the other stuff you mention. Try and plan your visit on a day that the National Museum of Computing (on the same grounds, but operated independently with rather limited opening hours) is also open.
IMO the big news is that the printed parts are strong enough to do this. The printing processes I've seen so far result in parts that are too brittle to serve as anything except decoration or as mould masters.
Given the willingness of both parties to force a default, I suspect any attempt in this direction will be quickly torpedoed by House or Senate.
see Accelerando.
I see you've installed batteries. That would change the equation significantly, I suspect.
It used to be that solar panels were by far the most expensive part of an installation. At the moment, for an installation that can supply 1350 kWh/year, the panels cost E4500, the inverter is E1200, labor is in the region of E1000 as well I suspect. So the panels are still 66% of the total cost. Two years ago, the panels would have cost E8500, or more than 80% of the total cost. When the cost per Watt reaches E1, the panels will be 50% of the installation cost.
At that point savings in the cost of inverters and installation will become more critical than they are now.
According to Wikipedia, a change in inclination is the most costly type of changing your orbit.
I meant it would take a huge amount of fuel to change the orbit of the ISS.
The difference is that the US has chosen not to pursue the Shuttle program, so that the money can be spent on never ending social programs.
Yes, social programs like 2 simultaneous wars halfway across the globe, and paying interest on the national debt.
There ware good technical reasons to end the Shuttle program. The Shuttle configuration is flawed, and no amount of updated components is going to change that. It was time for a clean sheet.
The US is on its way to being able to provide Saturn V-class launches again. Only this time it's a private company instead of NASA. That's not a bad thing.
Wouldn't that take a huge amount of fuel?
Missions that are too heavy to fit within the load envelope of Dragon don't necessarily need a Shuttle. ISS modules and other heavy infrastructure can be lofted on an unmanned Falcon 9 (or Falcon 9 Heavy, if you really need to shift some weight). Between Dragon, ATV and HTV the need to bring equipment racks to the ISS is covered.
Satellite repair has been done 10 times, 5 of which were to Hubble. The cost of these missions was so high that it's generally cheaper to launch a new satellite than to send up a Shuttle to repair it. Similarly, satellite retrievals have been rare. Both functions could be useful if a vehicle was available that can do this at 10% of the cost of a Shuttle mission. That should be the goal, not retaining the Shuttle.
Solar Cells, and Lightning Rods seem to be the only methods I can think of that produce electricity without the use a turbine/generator combo but neither are viable for wide spread use.
Is 17 GW 'wide-spread' enough for you? Because that's the amount of solar cell generating capacity installed in Germany as of 2010.
Solar cell prices have been dropping like a brick, and right now the payback time of a small-scale solar installation (~20 years) is shorter than the projected lifetime (at least 25 years).
The 'aside' you mention is actually the main point. Even the most efficient power plants top out at 60% efficiency. Assuming your house is heated with gas, not electricity, this means that the light bulb is slightly over half as efficient as your gas furnace.
For a recent (less than 15 yo) gas furnace over here (.nl) efficiency is in the 95%+ range, thanks to government incentives towards more efficient systems. Dunno about the US situation.
Also, heat and light needs don't overlap: you'll be running those same lights in the summer, when your AC will be running overtime to pump out the excess heat from the damn bulbs.
Finally, the effect of light bulbs on heating is negligible. My central heating is rated at 25 kW, and I have 13 light fixtures. If I installed 100W incandescent lights everywhere I would generate ~1300W in heat, or 5% of the peak capacity I need.
sonic booms indicating Atlantis has gone subsonic.
Do they? AIU, the sonic boom is generated as long as the aircraft is supersonic. So the booms recorded on the video merely indicate that Atlantis was supersonic at some point close enough to the camera. The point where speed drops below Mach 1 cannot be determined from that.
The video shot by Castillo highlights a problem that occurs when you shoot video with the sky as its background, or in the dark: you have no reference frame for the movement of the camera, so it becomes difficult to judge what you're seeing. Case in point: in this video, the camera zooms in and then pans along the flightpath, making it look like the Shuttle changes speed.
The same problem happens in e.g. video of an airplane doing aerobatics: you can't separate the movement of the airplane from the movement of the camera.
I used to play flight simulator games, and these showed that there's a simple solution to this problem: show azimuth and elevation markings along the edges of the screen; this makes it easy to see that the camera is moving. With today's accelerometers, it should be possible to add this functionality to a camera...
I'd rather enable users and deal with the shit than treat them like peons and have them come to my ivory tower for their every need.