Mainland reports 9.9 MW battery storage of operating nameplate capacity. These technology ratings do not establish a common export limit. Source: EIA Aug 2026.

What kind of plant is Mainland?

Mainland is a batteries facility in Galveston County, TX, participating in the ERCOT market.

Where is Mainland located?

Mainland is in Galveston County, TX, inside the ERCOT balancing area.

Who operates Mainland?

Mainland is operated by HEN Infrastructure, L.L.C. according to the EIA generator inventory. Reporting membership does not by itself establish ultimate ownership.

How much electricity does Mainland generate?

Mainland reported 400 MWh over the twelve months to 2024-12. For a storage plant this is reported gross generation — a discharge proxy, not a cycle count or a conventional capacity factor.

How does Mainland compare to other plants?

By capacity, Mainland ranks #554 of 1,061 operating plants of the same technology nationally. It ranks #165 of 254 in TX.

Mainland — 10 MW battery storage, Galveston County, TX

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Mainland — 10 MW battery storage, Galveston County, TX · Ask the Grid

Generation and physical site

EIA plant 67494 · Inventory for Aug 2026.

Reported operating nameplate by technology

Battery storage: 9.9 MW

Operating generators only. Battery power is in MW; stored energy is in MWh. These ratings do not establish a shared export limit.

Generator records (1)

EIA generator status and nameplate capacity for Mainland
Generator	Technology	Status	Power (MW)	Energy (MWh)
MLNDB	Batteries	Operating	9.9	9.9

Physical map location · OpenStreetMap: 29.39588, -95.04081
Filed location · EIA: 29.39521, -95.04077

Sources and observation dates

Inventory source: EIA-860M workbook (preliminary)
EIA reporting month: Aug 2026
EIA retrieved: Oct 10, 2026
OSM extract: Oct 9, 2026
OSM last mapped edit: Nov 12, 2025
Map prepared: Oct 10, 2026
Field verification: Not reported

Reporting month describes the inventory. Retrieval and map preparation describe processing; an OSM edit does not establish an in-service date.

EIA source inventory

Units and generators

Operating generator records and technology attributes reported through EIA-860.

Generator	Capacity	Technology	Operation	Status
MLNDB	9.9 MW 9.9 MW summer	Batteries Electricity used for energy storage · BA	Jun 2024	Operating

Related parties and identifiers

Parties, market resources, and identifiers tied to this asset, with owner, operator, developer, EPC, compliance provider, and interconnecting entity roles kept separate.

Relationship graph

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AssetOrganizationFinancier

Parties and identifiers

OrganizationRoleBasis

HEN Infrastructure, L.L.C.Owner / operatorRegistered utility/transmission owner and power generation company

Manulife Investment ManagementFinancier / equity investorEquity partner for asset development

MAINLAND_ESR1Market resourcesLinked ERCOT resources.

Reporting portfolio

EIA reporting entity

HEN Infrastructure, L.L.C.

Entity 65076

Operating portfolio

31 plants

1 states

Reported capacity

317.3 MW

Batteries · Petroleum Liquids

Largest reported plants in this portfolio
Largest reported plants	Capacity	State
Olney	19.8 MW	TX
Toyah Power Station	10.4 MW	TX
Russek	9.9 MW	TX
Junction (TX)	9.9 MW	TX
Mineral Wells East BESS	9.9 MW	TX
Gomez	9.9 MW	TX
Caterina

Overview

Infrastructure record

Overview

Infrastructure record

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Structured profile

Generation and physical site

Reported operating nameplate by technology

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Units and generators

Performance

Peer context

Monthly generation

ERCOT disclosed dispatch

Dispatch

Output by hourlocal time · 90 days through Aug 23, 2026

Latest disclosed outputhourly · 2 weeks ending Aug 23, 2026

Settlement price economics

Grid and market context

Market registration

Operating context

Interconnection record

Nearby substations

Commercial, land, and environmental record

Transactions and agreements

Related parties and identifiers

Relationship graph

Parties and identifiers

Reporting portfolio

Timeline and sources

Project timeline

Sources

Common questions about Mainland

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What kind of plant is Mainland?

Where is Mainland located?

Who operates Mainland?

How much electricity does Mainland generate?

How does Mainland compare to other plants?

Co-located assets