Hosting Capacity & DER

Overview

Hosting capacity refers to the amount of Distributed Energy Resources (DER) — primarily rooftop solar, batteries, and EVs — that can connect to a section of the distribution network without requiring network augmentation. As DER penetration accelerates, DNSPs must actively manage hosting capacity to avoid voltage and thermal violations.

Hosting Capacity Model

Energy Copilot calculates hosting capacity using a simplified hosting capacity analysis:

HC_zone = min(HC_thermal, HC_voltage, HC_protection)

HC_thermal = (Thermal_limit_MVA - Peak_load_MVA) × power_factor
HC_voltage = f(voltage_rise_limit, line_impedance, DER_power_factor)
HC_protection = limit based on fault current increase

Thermal Constraint

Thermal hosting capacity is limited by the current-carrying capacity of the lowest-rated asset in the circuit:

def thermal_hosting_capacity(
    circuit_thermal_rating_mva: float,
    peak_demand_mva: float,
    diversity_factor: float = 0.85
) -> float:
    """
    Available thermal headroom for DER export.
    Diversity factor accounts for non-coincident peak export.
    """
    headroom = circuit_thermal_rating_mva - peak_demand_mva
    return headroom / diversity_factor

Voltage Constraint

Solar PV export raises voltage. The voltage rise is proportional to the exported power and the network impedance:

ΔV = P × R + Q × X  (simplified)

When the voltage rise exceeds the 10% statutory limit (AS 61000-3-3), additional DER cannot connect without network augmentation or export limits being applied.

Dashboard Pages

Hosting Capacity Map (/dnsp/hosting-capacity/map)

• Geographic heat map: available hosting capacity by distribution zone
• Colour scale: green (>50% headroom), amber (20–50%), red (<20%), black (at capacity)
• Layer toggle: thermal constraint vs voltage constraint (shows binding constraint by zone)
• Filter by voltage level: LV (415V), 11kV, 22kV, 33kV

Screenshot: Hosting capacity map showing a metropolitan area with colour-coded zones indicating available DER headroom.

Curtailment Risk Analysis (/dnsp/hosting-capacity/curtailment)

In zones at or near capacity, new DER connections may be subject to export limits or curtailment. The platform assesses:

• Zones where export limits are currently applied
• Percentage of time solar PV is likely to be curtailed (based on generation profiles)
• Revenue impact on solar owners: estimated lost generation revenue from curtailment
• Network augmentation cost to avoid curtailment: capex required to remove export limit

DER Connection Pipeline (/dnsp/hosting-capacity/connections)

Tracking DER connection applications in the pipeline:

• Application ID, address, technology, capacity (kW)
• Current status: application → technical assessment → approved → connected
• Aggregate impact: capacity waiting to connect by zone
• Estimated time to connection

Battery Storage Hosting

Grid-scale batteries require additional analysis beyond simple export capacity:

• Charge import capacity: batteries charging can cause significant import spikes
• Rapid ramp capability: fast-ramping BESS can cause protection coordination issues
• Harmonic injection: inverter harmonics can affect power quality

# Battery hosting capacity assessment
POST /api/dnsp/hosting/battery-assessment
{
  "zone_id": "BANKSTOWN_11KV_F04",
  "battery_capacity_kwh": 500,
  "battery_power_kw": 250,
  "charge_profile": "overnight_solar_arbitrage"
}

# Response includes:
# - thermal headroom for charge and discharge
# - voltage impact assessment
# - protection system compatibility flag
# - recommended export limit (if any)

DER Export Management

For zones at capacity, Energy Copilot supports dynamic export management:

• Static export limits: kW limit applied to all inverters in a zone
• Dynamic export control: inverters reduce output when zone voltage reaches threshold
• Tariff incentives: time-of-use signals that shift DER export to low-risk periods

# Set export limit for zone
POST /api/dnsp/hosting/export-limit
{
  "zone_id": "MANLY_415V_F03",
  "export_limit_kw": 3.0,
  "effective_date": "2025-04-01",
  "reason": "Thermal constraint binding during summer peak export"
}

API Endpoints

# Hosting capacity by zone
GET /api/dnsp/hosting/capacity?dnsp=ausgrid&voltage=LV

# Curtailment risk analysis
GET /api/dnsp/hosting/curtailment-risk?dnsp=sa_power_networks&threshold=10

# DER connection pipeline
GET /api/dnsp/hosting/connections?dnsp=energex&status=pending

# Zone utilisation history
GET /api/dnsp/hosting/utilisation?zone_id=BONDI_JUNC_LV&period=90d

# Hosting capacity trend (monthly)
GET /api/dnsp/hosting/trend?dnsp=essential_energy&months=24