---
title: "Negative price analysis for §51 EEG 2023 compliance"
method: POST
path: "/api/german-grid/negative-prices"
tags: ["German Grid Data"]
---

# Negative price analysis for §51 EEG 2023 compliance

`POST /api/german-grid/negative-prices`

## Request

- Base URL: `https://api.cernion.de`
- URL: `https://api.cernion.de/api/german-grid/negative-prices`
- Auth: none declared

Analyze negative price periods for EEG direct marketing compliance and prosumer advisory. **Critical for §51 EEG 2023 compliance.**

**§51 EEG 2023 Regulation**:
- **No compensation** during ≥6 consecutive hours of negative spot prices
- Applies to: EEG direct marketing (Direktvermarktung)
- Affects: Installations in direct marketing, prosumers considering switch
- Penalty: Zero compensation for entire negative price period (can be €100-500+ loss per event)

**Logic Parameter (consecutive hours)**:
- **1 hour**: Any negative price (strictest - for sensitivity analysis)
- **4 hours**: Pre-warning threshold (monitor market conditions)
- **6 hours** (**DEFAULT**): §51 EEG 2023 legal threshold
- **15 hours**: Extreme events only (rare, <5 events/year)

**Use Cases**:

1. **EEG Direct Marketing Compliance** (energy suppliers)
   - Track zero-compensation periods
   - Calculate financial impact (MWh affected × market value)
   - Risk assessment for new direct marketing contracts
   - Monthly compliance reporting to customers

2. **Prosumer Advisory** (self-consumption vs. direct marketing)
   - Risk evaluation: "Is direct marketing worth it for my 30 kWp installation?"
   - Calculate: (EEG revenue gain) - (negative price penalties) - (direct marketing costs)
   - Decision support: Stay in fixed feed-in vs. switch to direct marketing
   - **Critical threshold: <10 events/year = safe, >20 events/year = risky**

3. **Risk Management** (energy suppliers)
   - Identify high-risk months (typically: Mar-Apr, Oct-Nov = high wind + low demand)
   - Portfolio exposure: Total installed capacity × negative price hours
   - Hedge strategies: Battery storage, demand response, curtailment agreements

4. **Market Analysis**:
   - Negative price frequency trends (increasing = more renewables, more risk)
   - Seasonal patterns (spring/fall = highest risk due to wind + low demand)
   - Geographic differences (northern Germany = more wind = more negative prices)

**Typical Negative Price Events** (Germany):
- **Frequency**: 10-30 events/year (≥6 consecutive hours)
- **Seasons**: Spring (Mar-May) and Fall (Sep-Nov) highest risk
- **Causes**: High renewable generation + low demand + limited export capacity
- **Duration**: Typically 6-12 hours, occasionally up to 24 hours
- **Price range**: -50 to -200 €/MWh (extreme: -500 €/MWh)

**Financial Impact Example**:
- 100 kWp installation in direct marketing
- 15 negative price events/year × 8 hours avg × 100 kW × 100 €/MWh market price
- **Potential loss: 12,000 €/year** if not managed
- Mitigation: Self-consumption during negative prices (reduces loss to ~3,000 €/year)

**Best Practices**:
- Monitor monthly (identify trends early)
- Advise prosumers: Direct marketing only if <15 events/year + >30 kWp capacity
- Include negative price risk in direct marketing contracts
- Combine with §14a EnWG controllable devices (reduce grid impact during negative prices)

## Query parameters

- `token` string

## Request body

- object
  - `dateFrom` string, required: Start date. ISO format (YYYY-MM-DD) or relative alias: `today`, `today+N`, `today-N`, `tomorrow`, `yesterday`.
  - `dateTo` string, required: End date. ISO format (YYYY-MM-DD) or relative alias: `today`, `today+N`, `today-N`, `tomorrow`, `yesterday`.
  - `logic` 1 | 2 | 3 | 4 | 6 | 15: Consecutive hours threshold (§51 EEG 2023 uses 6)
  - `includeEegCompliance` boolean: Include EEG compliance analysis
  - `format` 'json' | 'csv' | 'xlsx' | 'xls': Output format. "csv" and "xls"/"xlsx" trigger a file download.
  - `token` string: Optional Cernion MCP token for this request. Overrides CERNION_TOKEN when provided.

## Response `200`

Negative price analysis retrieved successfully

- object

---

[API](https://skmtc.dev/cernion/apis/cernion-energy-tools-api.md) · [All operations](https://skmtc.dev/cernion/apis/cernion-energy-tools-api/llms.txt) · [OpenAPI document](https://skmtc.dev/cernion/apis/cernion-energy-tools-api/revisions/cdb94473b538?raw)