I had a gasoline powered chipper/shredder when I lived in SF. It worked ok, but then I ran out of things to chip and shred. But it did make good mulch. And I didn't want to mulch things like Russian thistle, because those things will seed anywhere.
If I had smaller green stuff, I would have gotten one of those electric shredders.
But I did have a devil of a time getting my compost to start up. It was so dry that I had to water it every day, and even then I had problems.
If you've got a lot of green up there, I'd do one of those electric things, or lay the green stuff out and shred it with a mower.

Here is a link that might be useful: Desert Gardens

leafygreens,

I have a gasoline powered chipper/shredder, also. It's my second chipper/shredder as the first was stolen from my yard. I purchased both from Sears. The 2nd has plastic housing that the vibration from the operation of it caused to crack and warp. It is now in pieces on the floor of my garage, waiting to be put back together with the replacement parts. I would recommend looking for a chipper shredder that doesn't have plastic parts! Mine is 10 HP. I use the chipper/shredder year round to create mulch that I use all over my yard. I shred trimmings from bushes, leaves and lots of pine needles. The pine needles (from my parents mountain house) make the best mulch imaginable: attractive, keeps moisture up, weeds down, doesn't blow away, decomposes slowly and eventually adds a little acid to our alkaline soil. The mulch eventually gets worked into the soil and improves the arability.

I use a twin barrel system to compost yard and household vegetable waste. I am careful of what I put through the chipper or add to the compost. I won't use plants that reseed freely because I can't quarantee that my composter temps get high enough to kill the seed. With the barrel retaining the moisture, I rarely have to add water, even in my arid climate.