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James Gardner: Home > Work > Carbage


Anyone with even a basic interest in the news should be aware that climate change is real. Chris Adams and I are working on a project code-named Carbage to help monitor energy use in offices in such a way that the the carbon can be apportioned based on who was in the building when the energy was used.

The idea is to make carbon reduction as fun an effortless as possible and allow people to be green by trial and error and without any manual data entry or understanding of complex carbon models.

What makes our project interesting is the software platform which goes with it which not only allows members to opt in to see their energy use over time butalso encourages participation by allowing people in the building to give a virtual "cheer" to other members to approve of when they do things which help decrease the overall energy consumption. By tying our software in to other software the members use

The Pitch

By working together or encouraging each other to save electricity, individuals within a building can help reduce electricty use. We just provide the tools to make the energy visible so that office workers feel empowered to turn off devices which aren't being used.

How We Are Different

We are focussing on making it fun and easy for people to participate, not on solving all energy problems perfectly.


The technology is actually really simple. We use a small embedded Linux server such as the 1 watt bifferboard (or a Mac mini in the case of our prototype) to scan a network for personal wireless devices to work out who is in the room. We then use a current cost device or similar to measure the electricity consumption of the building every 6 seconds. Both sets of data are then sent to a server which aggreagates them to estimate energy consumption per person.

Incidentally we can also use any existing infrastructre the building might have to infer presence such as RFID cards (like the Oyster cards used on the London Underground) or access codes if your company happens to enforece their use but we don't need them.


2009-07-14 Completed the first paper prototype of our software interface. Here's the screen where office members can send halos to other people in the room for their good deeds:

Halos and Energy Graphs
Chris and I also spent a day setting up a technical prototype in his house
2009-06-17 Began looking in detail at the relative merits of reduction, offsetting and Sandbag, an innovative idea to get people to buy up and destroy carbon credits to force the price of carbon to a sensible level.
2009-05-25 Entered our early thoughts to date about carbage into SiCamp. You can see our presentation here:
2009-04-30 Blogged about my first foray into the world of Carbon and Arduino with the Tea Light, a project to boil down (excuse the pun) the complexities of carbon to a simple yes/no answer to the question "Is now a good time to make tea?" by making a light glow red when the grid is under load and green when there is excess energy. The blog post has step by step instructions for building your own carbon saving arduino tea light.
2009-03-05 Visited the very first hackspace hack evening and learned about Arduino from Chirs and Peter.
2009-01-21 Tom Dyson gave a talk at Geek Night 12 about his site caniturniton.com which gives an answer based on the excess power in the national grid. He challenged the audience to build a hardware arduino device to consume the feed. I've been experimenting with an Edimax board so planned to build a system with that instead.
James Gardner: Home > Work > Carbage