Interactive Time Series Dashboard

Electricity Demand Forecasting

A modern forecasting dashboard for analyzing daily electricity demand patterns, comparing ARIMA and ETS models, examining STL decomposition, and exploring short-term future demand projections.

ARIMA ETS STL Decomposition Daily Aggregation Interactive Plotly Charts
Best Model
Lowest error among evaluated models
Lowest RMSE
Rounded to 2 decimal places
Data Range
Coverage of the daily dataset
Forecast Horizon
30 Days
Short-term projected demand
Explore Demand, Models, and Forecast Behavior

This dashboard is designed to help users move from raw demand history to interpretable time-series components and model-based forecasting. It combines interactive charts with short explanations so the results feel easier to understand.

Full Daily Electricity Demand
This chart shows the full daily demand history after aggregating the original hourly PJME data. The highlighted band marks the recent window selected in the control panel, so users can connect the zoomed analysis to the full historical context.
Recent Demand Window
This filtered view focuses on the most recent portion of the series selected in the control panel. It is useful for examining local movement, short-term volatility, and recent seasonal patterns.

Why use daily demand?

The original data is hourly, but daily aggregation reduces noise and makes medium-term patterns easier to interpret. This is especially useful when comparing forecasting models and decomposition results.

What should you look for?

Look for recurring cycles, structural changes, spikes, and changes in recent variability. Those patterns often influence how well ARIMA or ETS performs.

Trend Component
The trend captures the smoother long-run movement in the demand series after removing repeating seasonal fluctuations.
Seasonal Component
The seasonal component shows recurring cyclical behavior. In this project, weekly structure is especially important after daily aggregation.
Remainder Component
The remainder contains the irregular portion of the series not explained by trend or seasonality. Large spikes may indicate shocks, anomalies, or model difficulty.

What is STL?

STL stands for Seasonal and Trend decomposition using Loess. It separates a time series into trend, seasonal, and remainder components to make the structure easier to interpret.

Why decomposition matters

A forecasting model often performs better when the structure of the series is understood first. Decomposition helps identify whether the data is dominated by trend, stable seasonality, or irregular noise.

How to interpret remainder

A smaller and less structured remainder suggests the main patterns were captured well. Large erratic remainder values may indicate difficult-to-predict movement.

Actual vs Forecasted Demand
Compare the observed demand series against the selected forecast outputs. This view helps assess whether ARIMA or ETS tracks the actual pattern more closely.
Model Accuracy Summary
RMSE measures the typical size of forecast errors, MAE measures average absolute error, and MAPE expresses error relative to the true scale of demand.

ARIMA

ARIMA models autocorrelation and differencing structure in a time series. It is often useful when the data shows strong temporal dependence and can be made approximately stationary.

ETS

ETS stands for Error, Trend, and Seasonality. It is often effective when the time series has stable level, trend, and seasonal patterns that can be smoothed over time.

How to compare them

The best model is not just the one that looks visually smoother. It should also minimize forecast error metrics and follow the actual series closely during the evaluation period.

30-Day Forecast
This chart shows the projected electricity demand for the next 30 days using the selected best-performing model, along with 80% and 95% prediction intervals to communicate forecast uncertainty.
Forecast Table
The table below provides the projected daily demand values used in the forecast chart.

How should forecast values be used?

These values are model-based projections, not guaranteed outcomes. They are most useful for planning, comparison, and understanding short-term expected demand behavior.

What affects forecast quality?

Forecast accuracy depends on how stable the recent pattern is, whether structural changes occurred, and whether the selected model captures the trend and seasonality well.

What is a time series?

A time series is a sequence of observations collected over time. In this project, electricity demand is observed repeatedly and modeled as a structured temporal process.

What is seasonality?

Seasonality refers to patterns that repeat at regular intervals. Electricity demand often shows repeated cycles due to behavioral, weather, and operational factors.


What does RMSE mean?

RMSE stands for root mean squared error. Lower RMSE means the forecast is, on average, closer to the actual observed values, with larger errors penalized more heavily.

Why compare models?

Different models capture different structures. Comparing ARIMA and ETS helps determine which approach better fits the observed demand dynamics in this dataset.


Project takeaway

This dashboard is not only a forecasting tool but also a learning interface: it connects raw demand data, decomposition, forecast comparison, and future projections in one interpretable workflow.