Hello,

I'm working on a project to design a system that basically turns off all non essential electrical appliances in the home when it is not occupied. The idea is to reduce energy waste caused by lights, TV's computers etc being left on accidentally.

So far i'm thinking that each occupant within the house could carry a small keyring sized device, and basically whenever the keyring leaves the building the system will automatically turn off all non essential devices and appliances. My background is more mechanical engineering than electrical so i'm struggling to figure out technically how this would be achieved.

Would it be possible to have the "keyring" connect to a wifi network within the home, then whenever the connection is lost, it could be assumed that the occupant has left? Then have something wired up to the fuse box to actually turn off selected switches?

The solution doesn't need to be perfect, just functional.
Any input is greatly appreciated,
thanks.

 

I see some potential problems.

Many electronic devices need power on continuously. The TV and video recorder need power to keep the clock running, for instance. The computer needs to be told to shutdown before the power is removed.

The worst one would be the refrigerator. It uses a lot of power that could be saved but... Do you really want it off when you leave for a long weekend getaway?

 

Welcome to AAC!
Interesting idea, but there are some practical problems to consider:
1) Apart from a few fixed appliances (room lights,fridge, central heating controller etc) most appliances are likely to be plugged in at variable outlets around the house, so controlling them from the fuse box isn't viable unless each outlet is fed via its own fuse.
2) Different occupants are likely to have different views as to what is 'essential'.
3) What happens if one keyring is taken out of the house but another remains in the house?
4) Everything turns off if the wi-fi goes down.

 

Good idea. How much power would the switch that does the on/off use? Older time-clocks use 5 watts so no use anymore to switch of a 5 watt led light.
Sameer Miranda

 

Hello,

I'm working on a project to design a system that basically turns off all non essential electrical appliances in the home when it is not occupied. The idea is to reduce energy waste caused by lights, TV's computers etc being left on accidentally.

So far i'm thinking that each occupant within the house could carry a small keyring sized device, and basically whenever the keyring leaves the building the system will automatically turn off all non essential devices and appliances. My background is more mechanical engineering than electrical so i'm struggling to figure out technically how this would be achieved.

Would it be possible to have the "keyring" connect to a wifi network within the home, then whenever the connection is lost, it could be assumed that the occupant has left? Then have something wired up to the fuse box to actually turn off selected switches?

The solution doesn't need to be perfect, just functional.
Any input is greatly appreciated,
thanks.

If the device shuts down all the power when it senses that I left the house, how will it be powered to sense that I returned?

What is the net energy savings to have this extra device running all the time to sense that I am home, and the environmental impact of all the batteries on the device I would have to carry.

 

A lot of public buildings have IR motion sensors to power on the lights when someone enters the room. Then stay on for a time period that is reset when movement is detected. So a time after you leave the room, the lights go out. These are standard electrical fittings the you can buy over the counter.
Not as much fun as building your own, but fully speced and legal. That can be a bit of an advantage.

 

When I was a child ~65 years ago our house had one of those. It was called my dad. If we left our room without turning off the lights, he would take the bulbs from the fixtures. We learned real fast to turn off the non essential things. It stuck with me till this day, if leaving a room for more than a few minutes the lights are turned off.