URL: /guides/price

---
title: 'Price and Market Data'
description: 'Understanding electricity market pricing and trading data'
icon: 'dollar-sign'
sidebarTitle: 'Price'
---


## Overview of the NEM Spot Market
The National Electricity Market (NEM) operates as a centralized exchange where the Australian Energy Market Operator (AEMO) matches electricity supply and demand in real time.

- **Bidding and Dispatch**: Generators submit bids indicating the price at which they are willing to supply electricity. AEMO stacks these bids from least to most expensive and dispatches the least-cost mix of generators required to meet demand.
- **Five-Minute Settlement**: Since October 2021, the NEM settles on a five-minute basis. Generators receive the spot price for their electricity based on each five-minute interval.


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## NEM Price Caps and Floors
To manage market volatility and ensure reliability, the NEM enforces the following price limits:

- **Price Cap (Maximum)**: $15,500 per MWh
- **Price Floor (Minimum)**: -$1,000 per MWh

These limits define the maximum and minimum spot prices that can occur during any five-minute interval.

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## Market Value Calculation in Open Electricity

Open Electricity calculates the market value of electricity generation using the following methodology:

1. For each generator and interval, the value is determined by multiplying the electricity generated by the spot price in the generator's network region.
2. The total market value for a period is the sum of these values across all intervals and generators.

### Formula
Let:
- `g[i, j]` = Electricity generated by generator `i` in interval `j` (in MWh)
- `p[j]` = Spot price in the network region for interval `j` (in $/MWh)
- `N` = Total number of generators
- `M` = Total number of intervals

The total market value (`V`) is calculated as:

<latex>
V = \sum_{j=1}^M \sum_{i=1}^N \left( g_{i,j} \cdot p_j \right)
</latex>

### Explanation

- The formula aggregates the contribution of each generator during every interval.
- By summing across all generators and intervals, the total market value reflects the overall economic activity within the NEM.


# Price and Market Data

## Overview

Open Electricity tracks electricity market prices and trading data across Australian electricity markets, providing detailed price information and market metrics.

## Price Data Structure

### Core Price Components

Price data is stored in the balancing summary table with:
- Interval prices
- Dispatch prices
- Forecast prices

## Market Intervals

### Trading Periods

- `NEM`:
  - 5-minute dispatch intervals
  - Historical 30-minute trading intervals (pre-Oct 2021)

- `WEM`:
  - 30-minute trading intervals
  - 30-minute balancing market intervals

## Price Types

### Market Price

The market price is the price at which electricity is traded in the market.

### Market Value

`market_value` is a volume-weighted price calculated for each generator in each interval and then summed up to the total market value.