Bad news today for anyone who wants to get science kits for their children. Product safety for children is getting out of hand, the Consumer Product Safety Commission wants companies to perform safety checks on every item in science kits marketed to children.
I can tell you that these kits have been getting more and more dumbed down every year. Just look at a comparison from these kits from the 1960's versus these modern ones. Sure, the older ones are not as safe, but that is where Adult Supervision comes in.
This legislation of toys and products for children is getting out of hand. Sure, I want kids to be safe, but is up to the parents to choose wheter a product is safe for their child or not. We cannot prootect them against everything in the world.
So, parents, let your kids get a little dirty, let them get fingers pinched in the gears of dismantled toys, let them use the screwdriver. As an engineer, I am glad I got to tear things apart to see how they worked when I was young. It started my love for it and I'll let mine do the same.
Thursday, September 30, 2010
Page rename and an actual posting
Oh look, over a year of no posting! I promise to do better, really! Anyway, I have been busy with a couple projects and work. I'll try to post some up later. Just letting you know this blog isn't dead.
Thursday, May 7, 2009
Living Off the Grid
Today I came across a post on the IEEE (Institute of Electrical and Electronics Engineers) Spectrum site called "Living on 150 Watts". A couple in Fiji lives off the grid using a 300 watt micro-hydro turbine generator. There is not much drop (low-head) from the water intake to the turbine, so it only produces half the power it is rated for. The longer the drop, the more potential energy available, that is why hydro-electric dams are so tall (high-head). with only 150 watts you have to make a lot of sacrifices on what appliances they can use when. They plan on adding a methane powered generator to run off the methane produced by the rotting manure from their cows.
Hydro-Power
Here is a really nice example of a high head system. It is more complex than what you would use for a single household, but good for a small village or if you wan to go into it with your neighbors, it runs at about 8 Kilowatts.
A hydro system is nice if you have a stream running through your property, which not everyone has. Next up, power from poop.
Methane Power
Power production from methane is a fairly new energy production method. Dairy farms are really picking up on this technology, since you need a lot of manure to make enough bio-gas to run a farm, and if you have been to a dairy farm you know they have a lot. Methane production and power generation takes a considerable investment. You need anaerobic digesters, scrubbers to remove hydrogen sulphide and other impurities, these can cause increased wear on generators and engines that will be running off the bio-gas. Also needed is a generator or engine designed or modified to run off methane, or natural gas. The Caterpillar company already makes generator designed to run off "dirty" gas from unscrubbed methane. Here is a dairy farm that runs off it's own poo;
Wind Power
Wind power is one of those solutions that seems like a good idea, but is actually a pain in the rear. So many people think that there is some super efficient design out there somewhere that can power an entire house. Not true. Wind power is very finicky, you need an average yearly wind speed of at least 12 mph to get any viable energy. In Midwest states like Wyoming, North Dakota, and South Dakota, this is definitely possible.
Wind is a very finicky thing even in high wind areas. Too high wind speeds will break the wind turbine if it doesn't furl the blades (rotates the blades so they don't spin faster in the wind). This requires a more costly and complicated (read: breaks easily) mechanics. Plus you have to have a mast taller than anything surrounding it, like trees and houses. The best place to have one would be on a hill near Minot, ND. It always blows there ;)
Video of a catastrophic failure on a large turbine;
Solar Power
Ahh, solar. Not as over-hyped as wind power, but pretty close. Solar power has come a long way in recent years, especially in price. Solar is slightly less unreliable than wind unless you live in a desert area like Phoenix. Cloudy days drop the amount of energy available, and you get nothing at night from it. To get enough power to run anything decent in say Seattle, you need a significantly larger solar panel array than you would in Phoenix.
Back-up Systems and Miscellaneous Equipment.
All of these systems WILL require back-ups. failures either to the system, or source of the energy will occur (drought, cloudy days, no wind, generator malfunctions...). You need a back-up power source, like a battery storage bank or a gas/propane/diesel generator. A battery storage is always necessary for solar and wind systems, since it is unreliable. You need a way to store that energy you receive when you are not home and want it when you get back from work (usually in the evening when solar starts to conk out). Battery banks require a charging system to convert power from the source to a safe voltage and current to charge the batteries. If you are using "The Grid" (power company) as a backup, you must install a safety device that will cut your system from the grid in case of a power outage. This keeps the linemen safe from being electrocuted while trying to fix a line they thought had no power.
Unless you have everything in your house to run at 12V/24V/48V, you need an inverter. Inverters change the voltage from, say 12VDC batteries, to 120VAC that every home appliances runs on. Inverters can be cheap ones designed to run your laptop charger from the cigarette lighter in your car, to large expensive ones designed to run an entire household load.
Conclusion
Even with a large system producing lots of power, you may still find that you need to ration your power. With the kind of alternative energy system most people can afford, that will be a certainty. So, if you want to live off the grid, you must be ready to make a large initial investment and willing to make sacrifices in how much power you use, which is something you should do anyway, if not for energy conservation, at least your pocketbook.
Hydro-Power
Here is a really nice example of a high head system. It is more complex than what you would use for a single household, but good for a small village or if you wan to go into it with your neighbors, it runs at about 8 Kilowatts.
A hydro system is nice if you have a stream running through your property, which not everyone has. Next up, power from poop.
Methane Power
Power production from methane is a fairly new energy production method. Dairy farms are really picking up on this technology, since you need a lot of manure to make enough bio-gas to run a farm, and if you have been to a dairy farm you know they have a lot. Methane production and power generation takes a considerable investment. You need anaerobic digesters, scrubbers to remove hydrogen sulphide and other impurities, these can cause increased wear on generators and engines that will be running off the bio-gas. Also needed is a generator or engine designed or modified to run off methane, or natural gas. The Caterpillar company already makes generator designed to run off "dirty" gas from unscrubbed methane. Here is a dairy farm that runs off it's own poo;
Wind Power
Wind power is one of those solutions that seems like a good idea, but is actually a pain in the rear. So many people think that there is some super efficient design out there somewhere that can power an entire house. Not true. Wind power is very finicky, you need an average yearly wind speed of at least 12 mph to get any viable energy. In Midwest states like Wyoming, North Dakota, and South Dakota, this is definitely possible.
Wind is a very finicky thing even in high wind areas. Too high wind speeds will break the wind turbine if it doesn't furl the blades (rotates the blades so they don't spin faster in the wind). This requires a more costly and complicated (read: breaks easily) mechanics. Plus you have to have a mast taller than anything surrounding it, like trees and houses. The best place to have one would be on a hill near Minot, ND. It always blows there ;)
Video of a catastrophic failure on a large turbine;
Solar Power
Ahh, solar. Not as over-hyped as wind power, but pretty close. Solar power has come a long way in recent years, especially in price. Solar is slightly less unreliable than wind unless you live in a desert area like Phoenix. Cloudy days drop the amount of energy available, and you get nothing at night from it. To get enough power to run anything decent in say Seattle, you need a significantly larger solar panel array than you would in Phoenix.
Back-up Systems and Miscellaneous Equipment.
All of these systems WILL require back-ups. failures either to the system, or source of the energy will occur (drought, cloudy days, no wind, generator malfunctions...). You need a back-up power source, like a battery storage bank or a gas/propane/diesel generator. A battery storage is always necessary for solar and wind systems, since it is unreliable. You need a way to store that energy you receive when you are not home and want it when you get back from work (usually in the evening when solar starts to conk out). Battery banks require a charging system to convert power from the source to a safe voltage and current to charge the batteries. If you are using "The Grid" (power company) as a backup, you must install a safety device that will cut your system from the grid in case of a power outage. This keeps the linemen safe from being electrocuted while trying to fix a line they thought had no power.
Unless you have everything in your house to run at 12V/24V/48V, you need an inverter. Inverters change the voltage from, say 12VDC batteries, to 120VAC that every home appliances runs on. Inverters can be cheap ones designed to run your laptop charger from the cigarette lighter in your car, to large expensive ones designed to run an entire household load.
Conclusion
Even with a large system producing lots of power, you may still find that you need to ration your power. With the kind of alternative energy system most people can afford, that will be a certainty. So, if you want to live off the grid, you must be ready to make a large initial investment and willing to make sacrifices in how much power you use, which is something you should do anyway, if not for energy conservation, at least your pocketbook.
Thursday, March 19, 2009
Interactive Climbing Wall
On Hacked Gadgets today, I came across an interactive climbing wall. This thing looks great for teaching new climbers where to put their hands. I can't tell you how many times I have had to keep yelling "No, your OTHER left hand!" while trying to belay. This would also be awesome for climbing competitions too where you have to use specific hold in a certain order.
Friday, March 13, 2009
Solar Charging and the Outdoors
Today I will show you some projects around the web for portable solar charging. First up is the Rain or Shine Solar Charger brought to you by Instructables.
This is a pretty decent charger in reality and I really like the pouch setup so you can put your cell phone inthere to keep it dry too. It uses a step-up/step down DC/DC convertor that helps you keep charging a cell phone, which need a pretty stable supply, which solar isn't. The total project would roughly cost $50-$80, but that is significantly cheaper than any off-the-shelf chargers that start at over $100 and are not waterproof.
Up next is a really crude, ugly, but really cheap charger titled Small Solar Charger.
It is an extremely simple solar charger that just puts a diode across the batteries so that they do not discharge back into the solar cells. This is a heavier and more fragile charger than the one listed above nor can it charge a cell phone directly. To add that feature, you would have to build the Minty-Boost, a USB charger that you use AA batteries to charge a USB device (cellphone, iPod, whatever...). The total cost should be around $10.
These are just a couple of the many DIY designs out there. I got both of these from Instructables.Com on of my favorite How-To sites. Solar chargers can get complex very quickly, but I like these two since the charge AA or AAAs. Many GPSs, cheaper MP3 players, small flashlights, etc. use these making these chargers fairly flexible.
Happy hacking!
This is a pretty decent charger in reality and I really like the pouch setup so you can put your cell phone inthere to keep it dry too. It uses a step-up/step down DC/DC convertor that helps you keep charging a cell phone, which need a pretty stable supply, which solar isn't. The total project would roughly cost $50-$80, but that is significantly cheaper than any off-the-shelf chargers that start at over $100 and are not waterproof.
Up next is a really crude, ugly, but really cheap charger titled Small Solar Charger.
It is an extremely simple solar charger that just puts a diode across the batteries so that they do not discharge back into the solar cells. This is a heavier and more fragile charger than the one listed above nor can it charge a cell phone directly. To add that feature, you would have to build the Minty-Boost, a USB charger that you use AA batteries to charge a USB device (cellphone, iPod, whatever...). The total cost should be around $10.
These are just a couple of the many DIY designs out there. I got both of these from Instructables.Com on of my favorite How-To sites. Solar chargers can get complex very quickly, but I like these two since the charge AA or AAAs. Many GPSs, cheaper MP3 players, small flashlights, etc. use these making these chargers fairly flexible.
Happy hacking!
Wednesday, March 4, 2009
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