how to make the 'best' forecast?

hello everybody. i have 3 months of electrical load data and i want to make the short-term forecasting. based on my interval of dates,for how many days is recomended to make the forecast? thank you.

[Shane]

UPT,

Your question is a little vague and I am not entirely sure what you are trying to accomplish. Could you provide an example of your current data along with what kind of output you are looking for?

[UPT]

Shane, thanks for answering and sorry for my english. i have 3 months of electrical hourly loads, from 1 July 2011-31 September 2011. based on my interval of dates, which is the best forecast to do? for example, forecast for 1 day, for 3 days or for a week?.

Answer 1

[Walter Roberson]

Is this industrial load or residential load? Residential is going to be quite influenced by weather, with possibly high mid-summer load (air conditioning) and possibly heading up again as temperatures cool. But it doesn't sound like you have data on externalities such as weather, let alone climate.

For example, our high here on Saturday just past was +29.6C, requiring air conditioning. The low Sunday night, 1 1/2 days later, was -1.9C, a 31.5C (56.7F) degree difference, which would have led to a load for residential heating. You could not reasonably have predicted that much of a temperature swing in two days without knowing something about the climate here.

[Javier]

Walter your comment make me think about something. ¿Do you know if there is a principal component analysis of electricity price? , and ¿ what are the variables associate to the component analysis output ? This result may help to make a better forecasting.

[Walter Roberson]

Sorry, I don't have any information on those.

The answer would be quite different where I am (where electricity prices are set by a quasi-government board ever 3 months) than it would be in parts of the USA that do a lot of spot-price buying. Electricity is generated in numerous different ways, and the prices of some of the ways are very sensitive to international politics. And there are situations where the price can be negative (in cases where there is temporary over-production and it is not cost effective to turn down production.)

Pricing and demand are not the same thing.