Greetings,
We are pleased to announce several changes to our forecasting algorithms which were implemented this weekend. Most of these changes were around forecasting stream flows around the current water year.
Model Changes
- Water Supply. We are now using multiple basins (NRCS-based) per hydro station. Each station has a unique water supply forecast which projects out flows through the current water year (Sep 30, 2017). We will continue to use STP for days 10 to 60 and then phase out the RFC numbers with our internal forecasts. Forecasts beyond 9/30/17 will be based upon normal snow conditions.
- Broke out non-ISO BAs. Our SP and NP forecasts will no longer include supply and demand from the four non-participating California Balancing Authorities (LDWP, IID, BANC, TID); all four of these have been grouped together in a hub we are calling “CalX”.
- Event Based Forecasts. In the past we ran the forecast in a perpetual loop, re-running all 27 months every time. Now the forecast runs whenever an input changes and only runs for the period effected by the change. For example, when the model collects the 12Z we will re-run 30 days; when the model collects new snow data we will rerun through Sep 30; if BPA updates it long-term TTC we will run for that period. When the model is not updating it will refresh natural gas prices and update power prices every fifteen minutes.
New Reports
- Snow Summary – a recap of six years of snow history aggregated into three groups
- By Snow Basin (made up of one or more snow stations)
- By Hydro Basin (31 used in Ansergy models reflecting 100% of the WECC hydro capacity); each hydro basin is mapped to one or more snow basins and a simple average is used to compute the water supply anomaly
- By Power Hub – seven Ansergy power hubs; weightings are based upon cumulative downstream capacity; for example. Hungry Horse has 21,000 MW of downstream capacity plus its own capacity; the plants on the Cowlitz have just themselves.
- Menu Location
- Snow Basins
- Hydro Basins
- Three Metrics:
- Snow and Precip are reflected as % of normal (100 = 100% of normal); Blend melds snow and precip together in the ratio of 80:20, respectively
- Sample Report
- Filtered on Pend Oreille, returned the three basins mapped into it
- Fields include capacity, elevation, and several measurements for the current year plus levels for the same day over the last six years.
- Sample Chart
- The current year is extended out through the balance of this water year using the last anomaly; note the extreme volatility in the front, at the start of the water year.
If you have any questions please call or email.
Happy Trading/hedging,
Team Ansergy