Anyone here "rewired" a standard house lighting system by using solar powered shed /landscape lights? So the system is no longer centralized (the panel just drilled to the outsideof each room or something? If so, how'd it work? I see it can be done for like $30/room and am tempted. I got some lighting for the outside of our home and was so impressed with the improvements since the last time I used solar for lighting I've been inspired.
I should also mention our power bill is about $100/mo and the average person here spends about 8% in lighting, so that means we're spending about $100/yr on lighting currently. The conversion would thereby pay for itself in 6 years if nothing needed subsequent replacement, or no replacement more than the cost of the light bulbs.
I doubt the garden lights (their battiers to be precise) will last 6 years, or produce enough light to be of much use.
A reasonably bright LED lamp requires 3-10W. To keep a 6W LED running for 5 hours (which I find not enough), it needs 30Wh. This is the capacity of a 10Ah LiFePo4 cell. (cost 10€). The average garden light will have a much smaller battery.
Another problem is that during winter, when most artificial light is needed, the batteries are charged the least. The tiny solar cell of a garden light is not nearly enough.
If 92% of the energy is not spend on lighting, it sounds like there are better opportunities to save energy.
EDIT: The first step in this direction would be to find out, how much light is used and how long.
It wouldn't hit the $30 per room threshold , but a centralized 12v battery with a solar panel and charge controller should easily meet and exceed your requirements for lighting. Plus other features like charging phones and laptops. The great thing is expandability. 3 batteries and an invertor and now you are vacuuming with it, or making coffee, running your computer, watching tv......
I guess it depends on the end goal. If the solar lights leads to wanting to do more, plan for the more from the getgo.
Yes, I suspect we will want to fully convert, but a decentralized system intrigues me because of its ease, flexibility, and scalability. I'll have to see how these things react in winter. I got a 3 pack of lights and only needed 1 for outdoor lighting, so I have left 1 in an equator-facing window and one in a west facing window. They are on the inside, because I wanted to test their limits. The one facing south was a great night light level of light for a 15x30 room. The one to the west was not impressive, though you could see near it.
I'm trying also this "weird" idea of letting my eyes adjust to natural light versus flipping the switch every time I enter a room. Our natural light in summer is awesome. Winter snow reflection actually acts like a night light here.
Some of these outdoor lights run on AA rechargeable batteries, which cost like $15 to replace when they go bad. Not sure how long that takes.
Our major appliances are all probably higher amperage than the sun power we get here too, so I'm not sure a centralized system would be worth it for us.
I have a few bicycle lights, that are nothing more than a 1W led and a resistor connected to one LiIon cell.
It is definitely usable to read a book – for an hour or so until the battery voltage has dropped to 3V.
(The current drops as the battery voltage drops, so it doesn't just turn off, but gets gradually dimmer.)
Assuming the LED requires 1W, and has to run at least 10 hours per charge, that is 10Wh.
Assuming effective 2 solar hours during winter, it would require a 5W solar panel too keep it charged. (and overcharge protection).
Assuming 10% efficiency of the panel, it would require about one half square foot of (good) solar panels. (or 20cm * 25cm).