# Overlay and Grid 1
> Overlay membership without a perimeter, NERC/FERC/TSO non-interference, coordination without prices, and v26.0 energy-in-the-interval scope.
- Repository: g2tf-org/g2tf-standards
- GitHub: https://github.com/g2tf-org/g2tf-standards
- Human docs: https://grok-wiki.com/public/docs/g2tf-org-g2tf-standards-436ba3f3e0ff
- Complete Markdown: https://grok-wiki.com/public/docs/g2tf-org-g2tf-standards-436ba3f3e0ff/llms-full.txt
## Source Files
- `architecture/overview.md`
- `architecture/design-principles.md`
- `architecture/temporal-position.md`
- `architecture/failsafe-model.md`
- `README.md`
---
---
title: "Overlay and Grid 1"
description: "Overlay membership without a perimeter, NERC/FERC/TSO non-interference, coordination without prices, and v26.0 energy-in-the-interval scope."
---
Grid 2 is a voluntary **orchestration plane** on the existing physical grid (**Grid 1**). The plane is an **overlay network**: coordinated by protocol, embedded throughout Grid 1, verified by aggregate footprint, with **no perimeter** and **no central operator**. Living architecture is `architecture/overview.md` (Draft — seeking input). The design table is `architecture/design-principles.md` (Informative). The immutable narrative is [RFC #1](https://github.com/g2tf-org/g2tf-standards/blob/main/rfcs/grid-2-rfc-1.pdf) (August 2026). G2P, GCAP, and DESP each version independently on the **26.x** line; current drafts are **26.0-draft**.
Grid 2 does not replace, modify, or bypass any Grid 1 mechanism. Participating assets continue to meet all **NERC**, **FERC**, utility, and **TSO/ISO** requirements in their existing Grid 1 context. The G2TF coordinates with those bodies; it does not supersede them (`GOVERNANCE.md`).
## Overlay model
The overlay is digital, not a second physical grid. Members sit at ordinary Grid 1 points of interconnection. They are **not** topologically separate.
Two element kinds implement the plane:
| Element | Role | Grid 1 binding |
|---|---|---|
| **Member Elements** | Digital representatives of Use (flexible load), Buffer (storage), and Source (clean-energy supply) | Bound to a physical POI; self-dispatch inside host-utility parameters |
| **Allocators** | Deterministic clearing agents for a constraint domain | Informed only by Grid 1 capabilities and constraints from the transmission owner and, optionally, the regional system operator |
Each one-minute interval:
1. Members broadcast Service Descriptors (per-class consume positions, Buffer charge/discharge offers, Source supply offers) via **G2P**.
2. Allocators clear those descriptors against provisioned Grid 1 constraints via **GCAP**, using **DESP** class order.
3. Members **self-dispatch** the resulting commit-% / committed dispatch / committed take.
4. Members report **verified self-dispatch** so the overlay’s aggregate footprint is measurable.
Equitable dispatch is proportional to connection size and differential request size. The Allocator holds **no internal intelligence or discretion**.
```mermaid
flowchart TB
subgraph market["Grid 1 — Market Dispatch Domain ~5 min"]
MKT["Nodal pricing and forward dispatch"]
end
subgraph overlay["Grid 2 — Overlay orchestration plane 1 min"]
DESP["DESP — classification and priority"]
GCAP["GCAP — deterministic allocation"]
G2P["G2P — identity, messages, staleness"]
end
subgraph fast["Grid 1 — Fast Operational Domain seconds"]
FAST["Governor response, AGC, reserves, protection"]
end
market -->|"Grid 1 instruction prevails on conflict"| overlay
overlay -->|"MUST NOT interfere, substitute, or assume"| fast
```
Grid 2 commits only **above** the timescales where Grid 1 primary controls operate and **below** the market-clearing domain. Sub-minute response is out of scope for the orchestration plane.
## Membership without a perimeter
Grid 2 has **no admission process**. Anyone running a conformant implementation at a qualifying point of interconnection, inside a domain whose transmission-owner constraints are provisioned to an Allocator, **is** a member.
| Rule | Specification |
|---|---|
| Technical membership | **Spec compliance**, not registration |
| Growth | Vendors build to the published spec; the overlay grows by deployment, not central permission |
| Domain membership | **Voluntary**; can exist distinct from other grid and market requirements |
| Commercial terms | Enforcement of flex capabilities, class limits, and charging for Grid 2-enabled use stay in the domain agreement — **outside the protocol** |
| Authority | No Grid 2 element derives authority from the protocol. The protocol carries constraints whose authority comes from **Grid 1 custodians** |
The smallest Allocation Domain is one **host utility** plus one **flexible load**. That on-ramp is the transmission-owner **connect-and-manage** path: no capital deployment and no multi-stakeholder consensus. Grid 2 does not need to be universally applied. It sits inside the Grid 1 context at any scale.
Certification and conformance-test criteria for “spec compliance” are still open (`architecture/allocation-domains.md`). Commercial participation is not the same as technical membership.
## Non-interference with NERC, FERC, TSO/ISO, and Grid 1 controls
### Regulatory posture
| Body | Overlay relationship |
|---|---|
| **NERC** | Assets remain under existing reliability obligations. **CPS1/BAL** stay the balancing measures. Ancillary-service *sizing* can be tuned over time to observed need; the overlay does not rewrite the measures. **NERC CIP** applicability, key management, and replay protection are open Engineering discussion items and will be specified in G2P. |
| **FERC** | Adoption is voluntary inside existing rules. Broader FERC-level recognition is a later, post-proof step (RFC #1 §Phased Adoption). |
| **Utility / TSO / ISO** | Host-utility interconnection and ramp parameters remain binding. The transmission owner **MUST** provision Allocator constraints. A regional system operator **MAY** add capacity constraints to a regional Allocator. |
G2TF alignment work with **IEEE 2030.5** and related standards is tracked in Discussions. A companion regulatory/engineering document is in development; it is not a living spec in this repository.
### Operational MUST NOTs
From `architecture/temporal-position.md` and the failsafe model:
- Grid 2 elements **MUST NOT** interfere with, substitute for, or assume the function of sub-second primary controls (governor response, AGC, protection).
- Grid 2 **SHOULD** consume, not contradict, forward information from the market dispatch domain.
- Where a Grid 1 dispatch instruction conflicts with a Grid 2 allocation, the **Grid 1 instruction prevails**.
- On stale constraint inputs or partition, the Allocator **MUST NOT** clear. Members fall back to Grid 1 baseline.
- Peer Allocator announcements **MAY** add boundary headroom but **MUST NOT** relax local Grid 1 constraints.
Traditional **Firm (Grid 1)** service sits **outside** DESP. GCAP never curtails it. Classes **A / B / C** (Assured / Preferred / Best Efforts) stratify non-firm demand **above** that firm layer.
## Coordination without prices
Real-time coordination is protocol-only. Commercial settlements stay on Grid 1’s slower clock.
| Surface | What it does | What it does not do |
|---|---|---|
| **G2P** | Carries signed energy positions, commitments, federation announcements, telemetry | Does not price or settle |
| **GCAP** | Deterministic headroom → buffers → C-then-B-then-A curtailment | Holds no discretion and no bid stack |
| **DESP** | Class taxonomy and mandatory curtailment order | Does not define tariffs or SLAs (per-class performance envelopes are open) |
| **Domain agreement** | Charging for Grid 2-enabled use, class-mix limits, flex enforcement | Not encoded as protocol messages |
This is the Informative principle **Coordination without prices**: technical protocols handle the one-minute plane; current commercial settlements remain decoupled.
## v26.0 energy-in-the-interval scope
Version **26.0** is focused on **units of energy consumed and provided within the one-minute window** on the **bulk power system**. G2P requires every Service Descriptor position to be expressed in those units.
| In 26.0 | Not in 26.0 |
|---|---|
| Energy in the interval (consume / charge / discharge / supply) | Other goal-seeks (e.g. **voltage support**) |
| Bulk-power Use, Buffer, Source, Allocator | Distribution-scale devices (future work building on **IEEE 2030.5**) |
| Whole one-minute allocations | Sub-minute orchestration |
| DESP A/B/C above Grid 1 Firm | Routing through advanced power electronics (**SSTs**, **HVDC**) |
| Source offers as a single supply class (mirroring A/B/C is an open item) | Protocol-native prices or market settlement |
Wire format, encoding, state machines, version negotiation, and conformance test vectors are **unspecified** in G2P §7. Do not treat 26.0-draft as an implementable on-the-wire contract.
## Verification without inspecting internals
Reliability is not a promise from a central operator. It is three properties together (`architecture/overview.md`):
1. **Local good-citizenship** — each asset, at its POI, follows the protocol and responds to locally observable conditions.
2. **Protocol-ensured consistency** — every member runs the same algorithm against the same observable signals.
3. **Aggregate observability** — Grid 1 measures system-wide effects and verifies the overlay is collectively net-positive.
Grid 1 custodians verify by **footprint**, not internals: frequency stability, ACE excursions, transmission flows, peak shaving. The Allocator never sees or directs workloads inside a facility; it clears class-level positions only.
G2P **MUST** authenticate Service Descriptors and Commitments. Transmission-level deployments are expected on **private networks**. Failure of the orchestration plane **MUST** leave the physical grid no worse than the pre-Grid 2 status quo: Use reverts to firm load limit or manual curtailment; Buffer reverts to its standalone Grid 1 schedule with **no** Grid 2 support commitment; Source reverts to Grid 1 interconnection behavior. All transitions follow agreed ramp rates.
## Open items that affect the overlay–Grid 1 boundary
These remain Draft — seeking input. They change interoperability, not the overlay definition:
- Intra-interval timing budget and clock-sync (G2P / temporal position)
- NERC CIP mapping, PKI, replay protection (G2P §6)
- Standardization of transmission-owner constraint signals (Allocator / Engineering discussion)
- Interaction with 15-minute settlement intervals and mid-interval market dispatch (GCAP / temporal position)
- Conformance tests for “spec compliance”
- Source class structure beyond single-class 26.0 supply
## Next
Interval clock, commit-before-open, and the Grid 1-prevails conflict rule.
Nested constraint domains, transmission-owner authority, and commercial terms outside the protocol.
Per-element Grid 1 baselines, interval-only commitments, and locally determinable fallback.
Required Grid 1 constraint set and the rule that peer announcements must not relax local limits.
DESP A/B/C above Grid 1 Firm and mandatory C-then-B-then-A curtailment.
G2TF roles and the explicit non-supersession of NERC, FERC, utility, and TSO/ISO requirements.