When I purchased by Brompton, I skipped the option of hub-dynamos and other toys, taking the position that what is on the bike must be carried, whereas battery lighting is incrementally upgradable and may be removed in summer.

In short: less weight to carry, less to go wrong, and batteries can be bought at any corner store in an emergency.

I found that I could mount a HL-EL130 upside-down beneath the handlebars, and that it would just touch the front wheel spokes with the bike folded. This gives me a removable-but-mostly-permanently-mounted headlight.

Similarly – because I use the extendable seatpost – I have 3″ of post onto which is lashed a TL-LD130 and a small tool-pouch, containing puncture kit, Topeak Alien 8 tool, and spare batteries in an old Kodak film canister. I can never quite fully-collapse the seat but that’s OK, it’s not been a problem for me.

The two lights came as a pair, conveniently, for about 25 quid.

This left the problem of what to do about proper lighting in winter; Simon pointed me at Evans cycles from whom I bought a Cateye Double-Shot – which is supplied with an abundance of mounting clips, the same fitting as my Cateye lights on the Hybrid and on the Trike – and it is rechargable, and literally brilliant. It’s not as good as Simon’s uber lights, but it was on reduction to 90-odd quid, and fits in with all the other stuff I’ve got.

I found that it is best mounted sideways on the handlebar uprights, giving instant beam-elevation adjustment.

In case this is unclear, photos follow:

My Brompton, parked on the platform at Fleet station

Semi-permanent HL-EL130, mounted upside-down; removable Double-Shot mounted sideways.
Note battery pack velcroed above headstock retainer lug which bears weight of batts.

Closeup

Underseat cannondale toolbag containing Alien 8 Tool; Cateye TL-LD130.