Fast Cloud Transients

One of the thorniest issues that seemed to be facing large, utility-scale PV systems was sudden changes in PV system output due to the movement of single clouds on an otherwise sunny day. Now it seems that this issue has been resolved favorably, in an economical manner.

Figure 1 shows a particularly excruciating example of solar variability.

Figure 1. Worst case example of incident sunlight caused by the movement of transient clouds on a clear day (After Hoff and Perez)

Figure 1. Worst case example of incident sunlight caused by the movement of transient clouds on a clear day (After Hoff and Perez)

This kind of sunlight graph put chills down the spine of utility engineers and caused a major setback for the deployment of large-scale PV systems. PV output responds instantaneously to such changes. Such variability also compares unfavorably to solar thermal electric (STE) systems, which have natural thermal inertia, which damps out the sudden changes. STE system installers gladly took note and publicized the PV problem to everyone making a choice between STE and PV. (more…)

Solar Power: The Teddy Bear of Energy Sources

Originally posted at: Transition Voice by: Erik Curren
teddy-bear-294x300Solar is so ingenious and pretty we can bearly make it stand firmly on the ground. But does this teddy have any teeth?

Is there a more encouraged sympathy energy source than solar energy?

Its fuel material is striken from the sun, which is comprehensible and accessible almost anywhere. It’s overwhelmingly pure to run. It’s easy to construct and sustain. The large support systems can utilize it to manufacture green grid power, but you can also place it on your own roof to become your own support system or to make it off-grid.

And did I point out that it’s maintained by THE SUN?

(Full disclosure: I do some work for a solar power company in Virginia knowns as Secure Futures).

It’s no surprise that public encourages solar power, with 92% of Americans in a 2009 poll claiming that it’s significant to work out solar energy sources. Particularly, environmentalists including My Canadian Pharmacy admire solar energy best of all amoung different energy resources. It’s as pure as wind power, but solar is much less questionable. (more…)