Building Systems as Economic Actors
Friday, February 15, 2008 at 06:17PM
Toby Considine in Enterprise Interaction, Markets and Innovation, Microgrids and Distributed Systems

Building system controllers are getting more like the VTEC engine of my car. Whenever I get a tune-up, my car runs rough for a couple days. The controller figures out what has changed, adjusts to things, and once again runs optimally. In the same way, building systems becoming self managing. Controllers from well known brands now tune their systems in the same way.

The next step is a wider awareness. Package systems are just beginning to track humidity and temperature, inside and out, build a knowledge of how long it takes to reach a new state. As we extend AMI (Automatic Metering Infrastructure) to the system, energy use to achieve or maintain each state will become part of the mix. Shortly after installation, system controllers will be understand their actual energy needs. After one year, and a pass through the seasons, this database will extensive.

When a Demand/Response (DR) event comes from the grid, each such system will know what energy it can cut with what consequences. A front end agent, negotiating with sub-systems using higher order (abstract) messages such as the BACnet Load Control object, will be able to assess the energy available for each behavior, compare it with the price offered by the utility, and decide whether to participate.

To take full advantage of the forward pricing under look-ahead DR, price awareness will need to move into the lower level systems as well. DR for load shaving is short term: I need you to shed power in the next 15 minutes. The more effective DR for load shaping delivers market prices for the day ahead.

Ventilation for building spaces today is dumb. This conference room holds 24 people, so always provide ventilation for 24 people. Existing business models schedule a meeting by inviting people and a room to the same meeting. There are systems that can adjust for occupancy already. What few of them have is a standards based way to communicate occupancy. If the room forwards this invitation to its systems, then the room can prepare for the seven actual attendees at this meeting.

With price awareness, the room can decide when to get ready. Is it better to prepare for the 9:00 meeting starting at 8:00? If energy is cheaper at 6:00 AM, perhaps cooling earlier and holding the room ready is the right decision today. The second option will certainly use slightly more energy. More importantly, it will push energy use from a time of relative scarcity to relative abundance. That movement, known as load shaping, will improve energy use across the bigger system. If the utilities price correctly, the cheapest solution is the better one for society and the environment.

Article originally appeared on New Daedalus (
See website for complete article licensing information.