The idea is that rather than just having electrical fuses within appliances to prevent the immediate and localised danger of electric shock, why not extend the notion of dangerous electrical consumption to the longer term and global significance by using natures own CO2 sinks as a mechanism to regulate our usage.
Each Natural Fuse unit consists of a houseplant and a power socket. The amount of power available to the socket is limited by the capacity of the plant to offset the carbon footprint of the energy expended: if the appliance you plug in draws so much power that it requires more carbon-offsetting than available then the unit will not power.
This immediate restriction on our non-essential energy usage that also connects us to the natural environment in some small way really appeals as a response to increasingly stretched resources. It also acknowledges that we will keep using our electrical toys .
However, having showcased a lot of concept designs that tackled similar issues in the Urban Gardening show I wonder how long it would be in the real world before this well meaning idea became an annoyance rather than a timely reminder. Perhaps this is merely a design detail that could be ironed out in development, but I'm more convinced that the answer not in a change of usage but a change of the source of our power.