Current Photovoltaics Applications—Transport

Summary

Transport applications were amongst the first to benefit from the potential for photovoltaic generation and still account for a major share of world markets. The variety of applications and demands provides a microcosm of the whole photovoltaic market. Uses span principal transport media and include marine and radio beacons, railway crossings and transport communications systems.

Transport networks inevitably span large areas and cross regions with no established electricity grid, so benefit particularly from the flexibility of photovoltaic power sources. This has enabled new advances especially in marine and rail transport.

Railway authorities, notably in Australia and Canada have used the high reliability and low maintenance of photovoltaic systems to pioneer new applications in their field. Free power availability in remote regions naturally enables crossings to be protected with lights, audible signals and barriers automatically controlled from tract circuit sensors all powered by a solar array. Station-to-station and station-to-train communications may also be energised from subshine.

Navigational aids, with their moderate intermittent power requirements are ideally suited to photovoltaic generation and such systems are already widely used. Experience in often hostile environments has contributed greatly to the supplier’s knowledge in designing equipment which can operate reliably in high humid and saline conditions. Battery design and overall system integrity has proved as crucial as module performance. Meanwhile the increasing competitiveness of photovoltaic devices has led to the viability of larger systems for radio beacons for example. Solar generators of a few kilowatts capacity are now seen to be economic for remote locations while moderate sizes are becoming viable even in inhabited areas.

Most transport systems demand high reliability as personal safety is often at stake. System design and overall integrity is thus the primary requirement. These factors are to be considered in detail. Users will demand and must receive exemplary engineering in these areas if the photovoltaics industry is to achieve its rightful place as a major energy supplier for transport applications.