Sunlight to grow room

Could I use a 12-inch bundle of fiber optic cable to carry sunlight concentrated using a lens and illuminate a garden with it? The initial cost might be high but there would be a terrific savings on energy costs.
Johnny B. Goode,
New Orleans, Louisiana

The cost of fiber optic cable would be fairly high and even using a fresnel lens to concentrate light you might need five or six 12-inch diameter cables to adequately light a 4′ x 8′ area. Fiber optic cables might be a little rich, but there are ways to move light from the roof to interior spaces. Sun or light tunnels consist of a lens shining light through polished metal tubes that guide it to indoor spaces. The tunnels come as large a two-foot diameter. A couple of large tunnels can provide an indoor garden with most of its light needs with little heat and no electricity costs.

Tunnel light has to be supplemented at dawn and dusk using electric lights to make at least 12 hours of light per day (for example, in winter). The garden may also need seasonal light supplementation because of short daylight hours or overcast weather, but most of the time, tunnels provide adequate light.

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