Keeping up the charge in a tail lift battery on a trailer can be an issue. Especially, if the trailer is swapped out between prime movers or left for periods unconnected. Charge is normally maintained by drawing a trickle charge down from the truck’s electrical system via the trailer connections.
A number of operators in the US are investing in an innovative solution using small solar panels stuck to the trailer roof to constantly trickle charge the tail lift battery even when disconnected from a truck. One of the systems sold in the US by eNow, is claimed to extend battery life by up to two years as well as ensuring the charge levels of the tail lift battery are always topped up.
In operations where trailers are regularly swapped, it is possible for a driver to pick up a trailer with a low charge in the tail lift battery and for the journey to a delivery point to be not far enough to give the truck’s electrical system time to recharge the tail lift.
A trial of this kind of system was carried out in Australia some years ago and found the economics of fitting the solar panel did not stack up. In the intervening period solar panel prices have reduced considerably and now may be a time to re-examine the issue.
The 900mm x 1000mm panels attached to the roof of each trailer are said to cost around $1000 each. Operators report a reduction in call outs to trailers with flat tail lift batteries, with US customer, DWS Fleet Management, quoted as getting a pay back on the investment within a year.