[RE-wrenches] Inverter Ramp times

[Ray Walters]

Fellow Wrenches;

I am consulting on a larger project out of country, and the utility is 
(as usual) concerned with disturbances to the grid from the variations 
in solar output.  I know that most of the latest utility scale inverters 
have some ability to control the rate that power ramps up and down, but 
what is the time scale?  Is it milliseconds, seconds, a minute?
Also, they are hankering for some type of storage, so beyond the 
inverter controls, what are some of the available short term storage 
strategies (2 to 4 hr) these days?  I've heard of several prototype 
large battery banks (and fires?)....
Anyone on the list have experience with these?

As always: thanks in advance for sharing your expertise,

-- 
R.Ray Walters
CTO, Solarray, Inc
Nabcep Certified PV Installer,
Licensed Master Electrician
Solar Design Engineer
303 505-8760