Consider installing your lights directly into the concrete when you want more outdoor lighting. You can do so easily--if you plan ahead. You will need to wire power to the positions where you plan to install the lights. Check with your local building inspector so that you are aware of all required codes before proceeding.
Have a certified electrician wire power supply lines from your existing power lines to the exterior location. Turn off the power to the supply lines before working with the power wires.
Excavate an 18-inch trench to the area where the light fixture will be placed. Install the conduit along the bottom of the trench, running the supply wires through the conduit and to the point where you will install the light.
Remove the internal components of the lighting fixture. You will install the housing in the concrete and then wire the fixture after the concrete has set. Position the light housing in the trench and use rebar to anchor it in place.
Pull all wiring through the entryway of the housing. Seal the wire entryway with duct-seal compound. Fill the conduit entry point with two-part potting compound. This protects the conduit and wiring from moisture.
Pour a minimum of 3 inches of drainage material into the bottom of the trench. Do not allow the drainage material to be as high as the light housing.
Pour the concrete into the trench, making sure the lip of the light housing is flush against the concrete. Allow the concrete to set.
Install the electrical components into the light housing. Install the correct lamp bulb and cover the lamp with the trim ring or protective cover, if included.
If you are not comfortable working with conduit, hire an electrician to prepare the light assembly before you pour the concrete.