Re: [smartpower-interest] [smartpowerdir] FYI OSTP requests input on SmartGrid

[Damir Rajnovic <[e-mail]>]

On Sun, Feb 14, 2010 at 12:22:25AM -0800, Fred Baker wrote:
> Where I have a problem, like you, is the idea that I'm going to spend  
> my day staring at the electric meter and make random changes at random  
> times at the whim of the utility. What makes a lot more sense to me is  
> the idea that the electric utility will give me (or my electronic  
> proxy) an idea today about pricing issues tomorrow, and I can set up  
> policies in accordance that intelligent devices in my home will  
> implement.

I would say that it must be my electronic proxy. The same way it is unlikely
for people to watch their meters all day long it is not likely that they
will review "power pricing forecast" every night and then make adjustments
to their equipment. We also have to bear in mind that these tarifs and
times are just forecast. If something significant happens in the grid
utility may shift times when price is low/high up or down.

So, instead of programming my devices in absolute times, I may want to use
a mechanism similar that is used for recording TV shows. I can see on TV
schedule that movie I want to record is after a sport event. But if the
sport event runs over then the movie will start that later. So, instead
of programming my recorder for some exact time I tell it to wait for the
movie code to be sent by the broadcaster and then start recording.

Now substitute "TV schedule" with "power pricing forecast" and "movie"
with "low tarif" and that is it. I can review if pricing forecast for
tomorrow/next week is acceptable to me and then decide to utilise it
or not. Having in mind that price forecast times may change my instruction
to the proxy may be "use low tarif for heating at all time except 
between 06:00-07:00".

> 
> BTW, a sudden wide-scale cut-off is bad for the electric utilities  
> too: imagine them sending out such a command, and within the next  
> hertz everyone changing their demand levels. Read RFC 3439 section  
> 2.2.2; the issues and arguments are much the same for the grid as they  
> are for the Internet.

Should we then introduce switch off/on interval to spread in time when
devices will turn off/on? We can give users ability to say "turn off/on
this device within an interval from <Start> and <Finish> time" and then
leave the proxy or meter to randomly select exact time when device
will be turned off/on. The only worry would be for all meters to pick
the same random number.

Thanks,

Gaus



> 
> But imagine that I was told yesterday (or even an hour in advance  
> today) that the price would be "low" most of today but between the  
> hours of <this> and <that> the price would be "high". With 24 hours  
> notice, I could decide to do my laundry in the morning, for example,  
> if that was a real issue. With even an hour's notice my home energy  
> controller could tell my air conditioner and my refrigerator/freezer  
> to control to a slightly lower temperature for an hour, and then at  
> the magic time (or five minutes before) it goes back to controlling to  
> the normal temperature. The refrigerator/freezer, btw, doesn't run the  
> defrost cycle during the high price interval - it waits until 12 hours  
> later or so. That has much the same effect of randomization without  
> either the square wave for the utilities or the stomach acid for me.
> 
> Alternatively, one could imagine the air conditioner having two  
> temperature settings, one for when power is cheap and one for when the  
> cost is high. I'll pay extra to keep the house below 90', perhaps, but  
> only cool to 78' when power is cheap.
> 
> Where this fits into the technical work is that the information models  
> for communications in the AMI (eg between the meter and the utility),  
> we need some way to have the utility able to say "the price between  
> <date/time> and <date/time> is <price> per <unit>".
> 
> It might look like this:
> 
> <tarrif_event>
>       <Start ss:Type="DateTime">2010-06-01T13:00:00.000</Start>
>       <Finish ss:Type="DateTime">2010-06-01T16:59:59</Finish>
>       <Price ss:Type="Float">0.50</Price>
> </tarrif_event>
> 
> be sent from the utility to the home energy controller aand be  
> interpreted in accordance with the contract with the utility, which  
> probably specifies the local currency as the unit of measure.
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==============
Damir Rajnovic <[e-mail]>om>, PSIRT Incident Manager, Cisco Systems
<http://www.cisco.com/go/psirt>      Telephone: [phone]
200 Longwater Avenue, Green Park, Reading, Berkshire RG2 6GB, GB
==============
There are no insolvable problems. 
The question is can you accept the solution? 

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