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  1. Joo, no 20 m/s ei ollut avomerellä. 15 m/s oli avomerellä Rauman edustalla. Jossain muualla avomerellä voi henkilökohtainen kokemus vaihdella.
  2. Tässä vähän vertailua start-stop-autoista: tavallinen lyijyakku ei kestä montaa viikkoa. Tämä nyt ei ehkä enää liity niin paljon alkuperäiseen tilanteeseen...

    http://articles.sae.org/10667/



    Although 12-V idle stop-start systems require robust starters or other sophisticated restart systems to operate on this voltage, the battery itself is the primary key to effectiveness. The less capable the battery, the fewer the number of times the engine can be stopped—it’s that simple. The conventional flooded-cell lead-acid battery (FCB) can perform the function perhaps for weeks.

    Fuel-economy improvements

    The two premium lead-acid alternatives are what are being used in Europe: an enhanced-flooded-cell battery (EFB) or the much more expensive but more capable AGM. The fuel-economy improvements vary according to car maker, but a BMW study estimates up to 4% overall for current systems, with the potential for 10% if a higher charge-acceptance-rate battery (over 100 A) were available. The present AGM charge acceptance rate is about 25 A, the exact rate depending on operating conditions, according to JCI, which estimates fuel-economy improvement of 5-10%.

    The EFB is reasonably capable for idle stop-start in economy cars with low feature content, such as the European versions of Toyota Yaris, Fiat 500, and Ford Fiesta ECOnetic. It has thicker plates and includes a polyester scrim plate that holds additional lead alloy and applies light pressure in the cell to minimize lead flaking losses. It has a cycling life that is double that of a conventional FCB, according to JCI.

    The AGM has 3-4 times the cycling life of an FCB, so despite its 100% higher cost, the AGM dominates. It takes more than 70% of the European idle stop-start market, with the majority supplied by JCI’s Varta brand, which also is the source for the 12-V battery in the Chevrolet Volt. The Kia Rio’s optional idle stop-start, first microhybrid in the U.S., has an AGM sourced in Korea, from Sebang Global Battery.

    The AGM is the only type known by AEI to be used in 12-V stop-start systems planned for the U.S. market. JCI also owns the OPTIMA brand, a spiral-cell AGM used on Corvettes, among other performance applications.