Your solar plant generates power. Your customer's facility is 50 km away. GRIDCO moves it.
Understanding the flow — and the charges — determines whether your open access solar economics work.
The GRIDCO flow
Step 1: Injection
- Solar plant connects to GRIDCO's transmission network (typically 33 kV or 132 kV)
- Power injects at your interconnection point
- SLDC (State Load Despatch Centre) meters injection
- Real-time monitoring. Ramp rate limits. Frequency compliance.
Step 2: Wheeling
- GRIDCO (or DISCOM, depending on draw location) wheels power through the network
- From injection point to your customer's draw point
- Transmission losses apply. Wheeling losses apply.
- You don't move electrons physically — you use the grid as a carrier.
Step 3: Draw
- Customer's facility draws from grid at their end
- Their DISCOM meters consumption
- They pay: solar tariff (to you) + wheeling + transmission + CSS (unless exempt)
You inject. GRIDCO moves it. Customer draws. You get paid for units generated.
The charges that add up
1. Transmission Charges (GRIDCO/SLDC)
Use of the transmission network. Typically ₹255/MWh (~₹0.25/kWh) for open access. Normative losses: 3% transmission, 8% HT wheeling. You lose 10-11% to losses before power reaches the customer.
2. Wheeling Charges (DISCOM)
Cost to move power through distribution. Varies by DISCOM:
- TPCODL, TPNODL, TPWODL, TPSODL — each has different rates
- Range: ₹0.02-1.20/kWh depending on voltage and DISCOM
- 25% exemption for renewable under OREP-2022
3. Cross-Subsidy Surcharge (CSS)
Industrial consumers subsidize agriculture/residential. Open access bypasses the pool. OERC charges CSS. ₹1.10-2.50/kWh for HT industrial.
Exemptions: 50% for state-commissioned renewable projects. Zero for GRIDCO demand aggregator structure. Verify with DISCOM.
4. Losses
Normative losses apply. 3% transmission. 8% HT wheeling. You inject 100 units, customer gets ~89. Net effect: your effective tariff needs to account for losses or you deliver fewer units than generated.
Why BESS changes the equation
Without plant-side BESS:
- Solar generates 6 AM - 6 PM
- You bank daytime units, customer draws at night
- Banking losses: 5-10% (monthly settlement)
- GRIDCO curtailment during oversupply — you lose those units permanently
- Ramp rate violations if generation spikes too fast
With plant-side BESS:
- Solar charges battery during day
- Battery dispatches in evening — extends delivery hours
- Less banking dependency — self-consume through battery
- Curtailment avoided — store excess, dispatch later
- GRIDCO compliance built in: Ramp rate control, frequency regulation, smooth injection
- CERC/SERC grid codes require this. Without it, plant can't inject.
Plant-side BESS is optional on Khurda open-access offtake (default is daytime solar). When you scope it, it helps with evening dispatch, curtailment, and smoother GRIDCO injection — worth modeling for evening-heavy loads.
Approval process — what to expect
Pre-requisites:
- Land secured
- Interconnection point identified
- Evacuation capacity confirmed with GRIDCO/DISCOM
- PPA or captive structure finalized
GRIDCO/SLDC:
- Application for open access
- Technical feasibility (evacuation capacity, stability)
- Agreement execution
- Metering and communication setup
Typical timeline: 3-6 months from application to approval, depending on evacuation readiness and documentation. Khurda Energy Park — interconnection approved. We've done the process.
Khurda Energy Park — GRIDCO in practice
48 MW solar in Khurda — BESS-ready. Grid interconnection approved.
We inject into GRIDCO. Customers draw at their facilities. We quote all-in — solar tariff includes our view of applicable wheeling/transmission. One number. No surprise charges.
Khurda is BESS-ready. Plant-side BESS available on request for evening delivery, curtailment mitigation, and GRIDCO compliance. OREP-2022 eligible for CSS exemptions.
Full 48 MW plant — offtake open Q2 2027. 5+ MW minimum. OPTCL feasibility complete; approvals received.
What your CFO needs to verify
Before signing open access PPA:
- Injection point and draw point — transmission path, losses
- Your customer's DISCOM — wheeling rates vary
- CSS applicability — 50% or 100% exemption?
- Banking rules — monthly settlement, loss factor
- Whether plant-side BESS belongs in your contract — depends on load profile (evening %, banking rules)
Get evacuation approval in writing. Don't assume capacity. GRIDCO and DISCOM confirm.
Request a cost model—we'll show injection to draw economics, applicable charges, and BESS impact on delivered cost.