Compressors: Oil-free linear compressor

Linear technology could become the predominant energy-efficient refrigeration compressor design, according to Brazilian manufacturer Embraco which unveiled a domestic compressor offering linear technology with variable capacity, eliminating the need for lubricating oil for its operation. The new compressor, which is the result of 5 years' research and a 20 million USD investment in the technology developed in conjunction with Fisher&Paykel (New Zealand), is said to provide energy savings of up to 30% against conventional technology. Being oil-free, the compressor allows more flexibility in its installation and positioning, whereas current compressors which contain oil must remain upright. LG has been using linear compressors - using oil - in many of its domestic refrigerators for nearly 10 years, but as Embraco's Vice President of marketing said "Beyond being an oil-free technology, our innovative solution uses half the amount of material when compared to other linear solutions, reducing its size and offering better performance." A linear-motor-driven compressor can be easily modulated, simply by varying the compressor stroke by means of a variable voltage power device. These are considerably less expensive than variable frequency devices. As there is no crankshaft, linear compressors suffer less friction loss and wear problems than conventional compressors.