I'm Judy Xu and I'm a graduate student researcher here at CTLC, and I'm helping with developing light control systems. We're trying to control the lights, like dimming up and down and off - turn them on, off. If you have enough daylight and then you just dim the lights.  That's simply put.  It's a daylight harvesting.  It's how we use the natural light to save energy.  So you don't have the electric light on all the day, just wasting energy, yeah. For example for the Wal-Mart projects and then they have limitations on their current technology for the light controlling.  And we come up with a completely new technology to control the lights in the Wal-Mart store.
 
This is the sensor prototype made by the watt-stopper. It's a dual sensor prototype with one sensor on this side and then the sensor in the back on that side. It's normally sits at a skylight like this.  So one sensor will be looking into the space and then the open loop sensor will be looking up at the sky.  We developed the control algorithm to make it controlling the lights according to the daylight. We can achieve them like three times better in light level consistency and also save them like 50 percent more energy.

And then now we are about to switch the entire control algorithm to the watt-stopper prototype to let it control the lights in the Wal-Mart store. We can save them like $1,000 each month per store, per Wal-Mart store. The payback will be just .2 years. .  It's really brilliant to bring the customer and the manufacturers together. We only help to develop products that will sell and also what customer really needs

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California Lighting Technology Center at UC Davis.