Topic: "Turn on when sufficient power available" (& back off) ... - page 2. (Read 1690 times)

Yeah exactly, but what I am asking about in this thread, is how it will automatically turn on and off in accordance with how much power the sun and/or wind actually happens to be putting out at any given moment.

Like maybe even one by one block eruptors coming online as the sun is seen directly, one by one going offline as a cloud passes the sun etc.

Or maybe have some small amount of battery to allow time for clean shutdown so its not on off on off too rapidly.

Maybe USB hubs that activate one plug at a time as enough power becomes available, instead of dividing the power in parallel across all plugs, stuff like that. So if there is only enough power for one eruptor it powers just one, instead of all of them failing to work due to only having a fraction of enough power each.

-MarkM-

I guess you didn't read the first post.

To get grid hookup for the house requires electrician signing off on the house's wiring.

Electrician wants the entire house gutted of all its nice antique plaster interior walls so he can put wiring behind the walls, then put up modern drywall crap as no one hardly anymore except maybe some specialist craftsmen even has the skills to do real plaster anymore.

It'd eat up easily $50,000 probably more just to get the house hooked up to the grid.

But, supposedly, off the grid solar power does not have all that crap about having to have a livable house etc, you can do it anywhere, a camp, a camper, a cabin, I know someone who lives in what amounts to a tent and has solar power.

So the whole point was, there is no grid, and batteries cost a lot, so maybe it'd be better to soak up excess power on sunny days using old inefficient mining gear like block eruptors or whatever than to buy enough batteries to store power to keep gear running 24/7.

Sure I am trying to talk landlord in town into letting me put solar panels on his roof and hook them into the grid.

But meanwhile I am still looking for ways to make use of my existing house out in the countryside that would cost way more than the house originally did to get its grid hooked up again.

-MarkM-

Hey Mate we're on the same page. Currently preparing a solar farm and wind turbines (diy version) to curb electricity costs and fire up my GPU miners again.

Batteries are expensive, solar panels aren't. So just measure your entire rig with a kill-a-watt meter and then you can figure out how much wattage you need and +20% allowance. You can use it for 12 hours during the day and probably 2-3 hours at night.

If you want to go the easier route, check out ebay. Ebay is full of cheap grid-tie power inverters that are capable of backfeeding power into your house's electrical circuits with a standard outlet plug. You plug it into the wall and connect it to your solar panel. When power is available it will backfeed into the house. Then you would just plug your little miner into an outlet as normal.

Note: I don't know how well they work or how legal they are to use, but a little 400W unit or something is unlikely to cause any issues outside of it maybe blowing up if a component fails

Assuming they actually work decently and you always have some load in your house consuming power equal to or greater than the power output of the solar panel, then you will offset your electric bill with the power generated by the solar panel.

You need a special agreement with the power company and a new electrical meter to have one that "spins backwards" and lets you sell money back into the main power grid.

So definitely it would be something custom then?

No off the rack power-switching boards with little screw-turned thingies you turn to set how much more power you want to be remaining after prior outlet is turned on before turning on next outlet kind of thing?

Hmm maybe some kind of thermal thing, stick it on one eruptor's heatsink, when it gets warm enough it turns on next eruptor, when that gets warm enough it turns on the next, etc?

Or hell with it if its so damn complicated maybe just turn on whole shebang when day/night porch-lights go off and back off when they go on... if those things can be tuned for how light or dark you want the day to be before they go on / off that might be all you'd really need?

-MarkM-

I've thought about this for the possibility of completely off-grid bitcoin mining myself.

My original idea was to have a small bank of supercapacitors. Once the sun rises, the panels would begin charging the capacitors. Once the voltage rises above the minimum required for the microcontroller it would boot up and begin testing if there is enough power available to begin mining. The supercapacitors would also provide a small amount of backup power in case birds or whatever fly over your solar panel for a few seconds.

Mosfet based power switching would be more efficient than relays since they do not require any significant amount of power to remain switched on vs a relay coil which wastes power in the electromagnet. I would set it up so the microcontroller has a few switched mosfet outputs, some for the actual load (say a raspberry pi and some block erupter USBs) and a dummy load (power resistor or semiconductor shunted regulator that draws approximately the same amount of power as each load stage)

The microcontroller would then switch on the dummy load for a period of time and watch the voltage of the supercapacitor bank. If the voltage sags below the operating threshold it would switch off and try again in a minute or so. Once there is enough sun to keep the capacitors above the operating voltage it would then switch on the actual loads and monitor the capacitor voltage in case of clouds, etc. You could add as many stages as you have outputs for the microcontroller assuming sufficient solar panel size

What would be required in order to power up gear - such as, say, USB block eruptors - as and when sufficient power becomes available, and shut down as power fades?

I am thinking that it could be nice to use solar panels for power but save on batteries by being able to use all the power when it is available.

I don't really have the option of hooking up to the power grid because doing so woudl require re-wiring a whole building, which would involve ripping out all the plaster inside so electrician can put wiring in the walls, then putting up gyprock drywall in place of the old antique plaster.

A bunch of gear is supposedly going to be too expensive to run one of these months because of the cost of electricity on the grid, solar using battiers gets pricey too because the batteries cost quite a bit, but I am thinking the old gear could be used to soak up excess power on bright days when the sun is pouring in more electricity than one has enough batteries to store.

Is there some kind of common rack of relays or chips or something one can get that turns things on in sequence as more and more power needs to be used, and back off as less and less power comes in?

-MarkM-