//TUTORIAL

Getting started with
run-of-river hydropower

Learn how run-of-river hydro is forecast in Erode - how generation follows natural inflow, which signals drive it, and how to plan operations and trades around the water you’ll actually have.

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BeginnerHydropowerGetting started
6 min to complete

What run-of-river means

Generation that follows the river, with little or no storage to buffer it.

A run-of-river plant generates from the flow passing through it at the time, with little or no reservoir to hold water back. Output rises and falls with natural inflow rather than being dispatched from storage, so what the river is doing largely sets what the plant can produce.

That makes inflow the single most important thing to forecast. When you know the water coming, you know the generation - and you can plan operations and market positions around it instead of reacting after the fact.

  • Inflow-driven - generation tracks the flow arriving now, not water banked for later.
  • Seasonal shape - freshet from snowmelt, summer recession, and rain-driven peaks each move output.
  • Operating limits - minimum flows, ramping rules, and hydraulic capacity cap how fast and how far output can move.
  • Spill risk - when inflow exceeds what the units can pass, extra water spills and that energy is lost.

Why inflow forecasts matter

Foresight on the water turns into foresight on the megawatts.

Because output follows inflow so closely, an inflow forecast is effectively a generation forecast. Erode builds that view from weather, snowpack, and hydrology for your site, so you can schedule, trade, and manage risk around the water you will actually have.

  • Scheduling - commit generation for the day ahead with confidence in the flow behind it.
  • Trading - place and size positions around expected high- and low-flow periods.
  • Spill avoidance - see rising inflow early enough to move water through the units instead of over the spillway.
  • Compliance - plan around minimum-flow and ramping obligations without being caught out by a surge.

Set up your run-of-river asset

Tie forecasts to your plant, its location, and its limits.

Add your plant as an asset so Erode forecasts the flow and generation for your exact site rather than the region in general.

  1. 1Ask the chat to set it up, or open the Assets area from the main navigation and follow the next steps.
  2. 2Add the plant as a hydro asset, placing its location on the river with the map input.
  3. 3Enter its remaining details, such as capacity, and choose the forecast types you’d like displayed on its dashboard.
  4. 4Save the asset - it is now available for the Analyst to reference in your questions.
Location on the watercourse matters most - it anchors the inflow signal to the catchment feeding your plant.
Learn more about assets

What to forecast

The signals that turn weather and snow into flow and generation.

  • Inflow - the flow arriving at your intake over the coming hours and days.
  • Snowpack - how much water is stored as snow upstream, which sets the freshet to come.
  • Precipitation - rain that can drive short, sharp inflow peaks on top of the seasonal trend.
  • Generation - expected output once inflow is mapped through your plant’s limits, plus any spill risk.

Ask your first question

Start from a decision you already make and let Erode do the digging.

Say you operate a run-of-river plant and want to know what to schedule for tomorrow. You could ask:

“What inflow and generation should I expect at my plant over the next 48 hours, and is there any spill risk?”

Erode answers with an expected inflow and generation range for that window, a short read on the weather and snowmelt driving it, and a flag if inflow could exceed what your units can pass - so you can schedule and move water ahead of the peak.

How to ask a great first question

Tips for sharper hydro forecasts

A few habits that keep your inflow and generation answers reliable.

  • Think in the catchment - conditions upstream matter more than conditions at the plant; ask about the basin feeding you.
  • Watch the freshet - through spring melt, check how snowpack and temperature are shaping the coming weeks.
  • Layer rain onto the trend - a passing storm can spike inflow well above the seasonal baseline.
  • Keep limits current - updated capacity and minimum flows keep generation forecasts within what you can actually run.
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