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Wireless Internet In An Off-Grid House
matt20 writes "This is an interesting article of a family living off-grid using solar panels. In such a setting, every watt adds up. The typical home computer and monitor use almost 150 watts. What is the best computer arrangement in such a setting? Here is what worked best for them. Anyone know what percent of our national power is used on computers? Should we be thinking wireless on laptops?" Even on-grid, this article raises some good points about power consumption and convenience.
With the number of devices in the home that now use DC power, I always thought it might save energy to have one large AC to DC transformer for the house, rather than having "wall wart" adapters for each device. Even when the device is off that wall wart is using energy(feel it, it's always warm). Why not have a more advanced transformer that could adjust for load, and run DC through wires to the whole house. Plus, no more problems trying to plug 2 wall warts into adjacent spots on a power strip!
Hardly. Buying your energy from a nuclear power plant will never net YOU, a homeowner, a net profit. Maybe if you live in the town that houses one you'll see something from their tax money.
;) But it does frequently exist, and a net zero or close to it for energy manufactured from a clean and renewable resource, for many, is maybe worth forgoing marble countertops.
If you aren't actually OFF the grid, most areas have a net metering program where you can sell excess power to the grid during the day and buy back power at night. This eliminates all the battery banks, a substantial chunk of the cost. If you furthermore design a home to be energy efficient to begin with, you can have an "affordable' solar system. I use quotes as it is undeniably a greater up front cost, but there is a return, though admittedly not much and it takes awhile to accrue.
If you ARE off the grid, then many people go with solar simply based on the economics of having a power line run to your home, if one doesn't already exist, can very quickly outstrip the cost of an entire solar electric system.
And for $1000 US or less, you can get solar hot water collection to at least augment your domestic hot water needs as well, with a definite payback period of less than ten years.
Not that payback is currently the best reason to go with solar. If someone hits a baseball into your panels, there goes your chance of payback for awhile
Interesting that I routinely deal with homes that will think nothing of spending thousands upon thousands of dollars to use Antique Jerusalem Stone on the floors, but mention Solar and the first question is, "what's the payback".
We did a study for one of my engineering classes recently about the power required to produce a solar panel as compared with the amount of power produced over the panel's lifetime. Turns out that manufacturing requires nearly 40% of the power the cell will produce over its lifetime. Kinda makes you want to look elsewhere, eh?
Actually, they are developing hydrogen producing bacteria. Check it out. More accurately, people are working on using existing bacteria to produce hydrogen. But eventually genetic engineering will probably be used to up the efficency of the process. Once you have the hydrogen, producing electricity from it is pretty trival (burn it in a turbine or fuel cell).
Some rough figures:
Some other fiures:
Industrial sheet metal shear: 3000 watts
Hydraulic press: 6000 watts
Industrial arc welder: 8000 watts
Commercial HVAC compressor (10 ton): 14,000 watts
A small, light industrial machine shop will have multiple of each of these. There are hundreds of these shops in almost every city in the US. Residential electricity usage doesn't even begin to come close to commercial usage. Computer usage doesn't even come close to the electricity used by these big tools. The last study that was done estimated that computers are using about 2% of the power consumed nation wide. That figure included networking equipment for backbones, and other office equipment like copy machines, too!