Store the Sun.

Store the Sun- External lighting can be expensive, as there are all sorts of regulations on how to install external cables safely (never attempt this yourself…Well, unless your a qualified electrician)
However there is a wide range of solar energy garden lights available in a vast array of designs. Provided you buy decent lighting with the British Safety Kite Mark, these are safe and free to run.
Harness the sun during the day and enjoy illumination in the evening. Admittedly they are not as bright as hard wired lighting, but do you or your neighbours want brilliant spotlights in your garden constantly?