The Department for Transport allows types of reflective and solar powered bollards on traffic islands and kerb build outs subject to regulations.
These can replace mains powered illuminated bollards and are cheaper, easier to install and maintain as well as benefiting the environment, as no mains electricity supply is needed. There is also the added benefit of the bollards' self-righting ability if struck by a vehicle.
This page provides information on the types of bollards that can be used as well as the regulations regarding their use.
Please note that in some circumstances, regulations require illuminated 'back up' signing to be provided in addition to reflective bollards. As mains power will be needed for these back up signs, any benefit from using reflective bollards may need to be assessed. Solar powered bollards do not require back up signing.
It is recommended that reflective and solar powered bollards be considered whenever opportunities for their use arise. The type of bollard chosen should depend on the individual circumstances of the location.