A better way to do interior lighting, without just buying fancy lighting fixtures.
American bulb socket sizes
The most common light bulb socket in America is called E26 (or less correctly E27). E stands for Edison and the number after it is the diameter of the screw socket. In practice E26 and E27 amount to the same thing. In America the other two types you will sometimes see in residential lighting are E12 (Candelabra) and E17 (Intermediate). The term ES means Edison Screw. The term MES means Medium Edison Screw which equates to an E26 or E27 socket. CES is Candelabra Edison Screw (E12) and IES is Intermediate Edison Screw (E17).
Rather than buy expensive light fittings I like to hide the lights so you cannot see the cheap ugly bulb holder and you don't get glare directly from the bulb.
If you have a sofit that hides the lights and wires then you can just put in a switched socket and then plugin a sting of lights.
The nice thing about this is that you do not have to meet electrical building code on anything after the switched socket and it is really quick to implement. The down side is that the light bulb physical positioning can be a bit random so the light pattern can therefore be a bit random. You can mitigate this with a plastic conduit U clamp on each bulb socket. Worth considering as a temporary implementation to get you to building signoff and then later you can repurpose the light strings for use in the yard. You might even decide to use it as a permanent solution.
Use 1" conduit clamps to hold each bulb.
In a power cut, if you have a 12V battery array, then it is the most efficient to use 12V bulbs rather than use an inverter to power 110V bulbs. The 12V battery can be charged from a solar array.
You need 12V lights in the soffits (in addition to 110V).
LED stick-on strips
This is the best bet.
Use 12V rather than using a power brick (they say they use 12V).
Trickle charge the 12V battery so that the lights are always battery backed.
Has the advantage of choosing whatever color you want, and also good for parties.
Currently the LED strips vary widely in color. It is assumed that this will get fixed with future products.
http://www.amazon.com/SUPERNIGHT-300LEDs-multi-color-Waterproof-Flexible/dp/B00AQT2G9S/ref=pd_sim_hi_1 Extension another 300 LEDs $13.99