Green Energy News | October 11, 1998

October 11, 1998 – Vol.3 No.28

ENERGIES... week of October 11,1998

POWER CATS. Not energized felines, but fuel-efficient powered catamaran yachts, sport, pleasure and work boats were showcased at the U.S Powerboat Show in Annapolis, Maryland this week. In the U.S. where energy consumption is largely ignored, recreational power boating is big industry. With all the talk about renewable energy, electric cars and other ways to reduce our fossil fuel consumption, there’s little talk about what to do about fuel-hungry power boats - until now.

The mantra of the power “two-hulled” boat builder seems to be “For the same length, at the same cruising speed, in the same class of boat - a power cat has 1/2 the fuel consumption and 1/2 the power requirements of a single hulled boat.” While this might not be exactly true for all current designs, performance numbers from a sampling of the boats shown in Annapolis closely approach that claim.

For the land-locked and those unfamiliar with marine design, the science is simple. Long slender hulls move more easily through the water than short wide ones - even if there are two or three hulls. Hull designs for the power cats include planing (plane-ing) hulls which ride on the water’s surface, displacement hulls which spend all their time in the water, semi-displacement hulls which plane with enough power, and wave-piercers with long extended bows to reduce lifting over waves.

The link between all the boats on display was that all the technology used to build and power them is off-the-shelf, already-proven technology: glass reinforced plastic (fiberglass) or other types of composite hulls; marine diesel inboards - with jet drive or propeller; four-stroke gasoline outboards - nothing particularly exotic or untested. The concept of multihulled boats themselves goes back centuries.

Manufacturers are also marketing the other good qualities of these designs: an air-cushioned ride with planing hulls (at speed air pressure builds-up between the hulls to virtually eliminate pounding); stability from hulls set apart; shallow draft for shallow waters; maneuverability and large deck space. (Cabin space below in larger models, however, is a design challenge.)

There are 50 or so manufacturers world-wide. Two of them are Glacier Bay Catamarans at http://www.glacierbaycats.com or World Class Catamarans at http://www.worldclasscat.com .

For an idea of design possibilities of these 21st century boats visit Jutson Yacht Design at http://www.jutson.com .