"Good lighting can make an ordinary kitchen look extraordinary and bad lighting can make an extraordinary kitchen unworkable."
Have you ever been in a kitchen with just a central fixture? Even if it is bright enough, it puts out broad shadowless light that gives the room a very utilitarian feel, also light at the counter never seems quite bright enough because the ceiling fixture is always behind you and there is no light on the task area. Alternatively, there are the kitchens where practically all the light is under cabinet task light. This approach can be very dramatic and stylish but the space will always feel dark because there is very little light on the face of the cabinets. Paradoxically having lots of task light on the counters makes the cabinets seem even darker.
In each of the above scenarios the lighting is done only half way. The first describes all ambient light and the second has only task light. Good kitchen lighting, from an aesthetic and functional standpoint, incorporates both types of light. A third type of light is accent light, with accent light points of interest are highlighted to give the space extra visual appeal. This method of layering the light is important for achieving positive results in all types of living and working spaces.
Start with the task areas. These are best lit with bright, shadowless light. Fluorescent tubes are particularly well suited for this because of their large surface area and high lumens per watt *1. You want to get the fixture close to the task area, (in kitchens this would be counters, sinks, and tabletops), so mounting the lights on the underside of the upper cabinets is convenient *2.
In the case of an island or peninsula counter top, with no upper cabinets to attach lights to, you need to use hanging, or pendant style fixtures to bring the light close to the task area. If this is not possible, you can project light from the ceiling (using either track or recessed fixtures) onto the task area.
The most effective lamps (or light bulbs) for track or recessed fixtures are directional lamps, these shine the light in a particular direction. The most efficient of the incandescent sources commonly available are the halogens. Halogen lamps come in line voltage (120 volt) and low voltage (12 volt). The low voltage lamps most often used are called MR16s. Be aware that these light sources have very defined beam patterns and cast hard shadows, which can make them a poor choice for a task light, but excellent for accent lighting (which I will touch on later). The line voltage halogen PAR30 lamp has a good blend of efficiency and performance so it is well suited for use in track and recessed cans used for task lighting. Since PAR lamps are line voltage, they do not require transformers like the MR16s and this can lower the cost of the system.
Think about ambient lighting. Ambient light is the general, overall light that fills in shadows, reduces contrast, and lights vertical surfaces to give the space a brighter feel. Ambient light is what you need for casual activities in your rooms. If the kitchen has light colored surfaces and lots of windows you should have plenty of natural ambient light during the day. But kitchens are used from before dawn until after midnight -- we can't rely on windows and skylights. Fluorescent tubes are well suited to the job of providing ambient light. They provide broad, even illumination and their efficiency makes it possible to really fill the space with light without using a lot of power or generating too much heat. Choose a color temperature of 3000K or 3500K for a warmer, more inviting appearance *3. You can put the tubes in a central fixture but you may want to try some other strategies, like placing them on top of the upper cabinets to indirectly reflect off a light colored ceiling. If you have at least 12 inches of space from the top of the upper cabinets to the ceiling, this is an inexpensive way to brighten up a kitchen. Or, maybe you have a custom pot rack hanging over an island and can build lighting into it to reflect off the ceiling and down onto the island.
Add a layer of accent lighting. Accent lighting is what gives our space a third dimension, adding to the quality of the space. Accent lighting is used sparingly on those special home objects that we want people to notice and admire. Accent lighting is usually done with spotlights, and the MR16 lamp mentioned earlier is one of the best. You may be lighting artwork, architectural details, collectibles, or food presentation areas. Remember, good lighting can make an ordinary kitchen look extraordinary and bad lighting can make an extraordinary kitchen unworkable.