In article ,
"Bob Mannix" writes:
I have seen a couple in garden centres (on). I wasn't really measuring but
hey seemed to give an equivalent amount (or more) of heat as a gas one in
one direction (more or less). A couple on a wall along a patio would
probably make a significant difference without occupying any footprint. They
might, of course, gently warm those the far side of a table and lobsterize
those closer!

The way global warming works is that on average they will heat the
whole world, but there are some parts which could get colder, such
as the UK if the Gulf Stream changed direction.

--
Andrew Gabriel