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Woodway Treadmills claim to be the most energy efficient.
In recent years, LG appliances have been made to be energy efficient. LG claims that it's third generation refrigerator compressor is the most energy efficient in the world.
The most energy efficient radiator heater is the oil filled one. A better option would be an electrical one because those are almost 100% energy efficient.
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The superlative of efficient is "most efficient."
Mostly this sort of thing is done through census returns.
there is no such thing as an efficient toaster so there can't be a lower efficient toaster.
Spur Gear is the most efficient
More efficient and most efficient are the comparative and superlative forms of "efficient".
A screw is the most efficient.
The cost of fuel varies considerably in different places; in some places it can dirt cheap, in others, as expensive as gold. Fuel is an interesting thing to consider when thinking of fuel-efficient SUVs- the most fuel efficient SUV is the Toyota Highlander Hybrid Limited.
ATP is the most efficient molecule
Heat is the most efficient agent of metamorphism.
most cost-efficient
Woodway Treadmills claim to be the most energy efficient.