"Services or tools available for free without requiring an API key" matching MCP servers:

Enables natural-language interaction with Ladybug Tools for building performance simulation, 3D modeling, and data visualization, allowing agents to perform complex environmental analysis tasks without CAD software.

MCP server providing deterministic, standards-traceable engineering calculations for combined-cycle power plant balance-of-plant design, such as fluid properties, pipe sizing, pump NPSH, and valve sizing, with every result including method, assumptions, and warnings.

Provides read-only access to Shelly Cloud energy data, including live power, lifetime energy, and historical consumption with cost, enabling AI agents to monitor electricity usage without device control.

87+ specialized tools for German and European energy data. Direct AI access to Marktstammdatenregister (MaStR), ENTSO-E, Redispatch 2.0, and Grid Operations for utilities and datacenters.

Enables exact residential electricity rates and itemized bills for Salt River Project, computed from filed tariffs with citations, via tools for listing plans, getting rates, and calculating bills.

Provides real-time electricity prices, cheapest hours, and contract comparison for 40+ countries, enabling AI agents to make energy-aware decisions.

Hourly electricity grid carbon intensity (gCO2eq/kWh) for 45 zones across Europe, the US and Great Britain, computed from ENTSO-E, EIA and NESO generation data. Four read-only tools; every value carries its interval timestamp and how stale it is. No API key, no account.

Live and historical electricity prices, demand, generation mix and carbon intensity for 25 grid zones (US, Europe, GB, Australia). Hosted endpoint plus local stdio bridge; free sample mode, free API key, or x402 pay-per-call.

Enables discovery and control of Philips Hue lighting devices via a local bridge using the CLIP v2 API, without any cloud dependency.

MCP server for fetching Danish electricity spot prices (DK1/DK2) using the free elprisenligenu.dk API, providing tools to get current price, cheapest hours, and price summaries.

The PGIQ Rating as agent tools: where to site or schedule a large electricity load across 67 global power markets. Wraps a read-only REST API returning reasoned, cited ratings across access, availability, cost, momentum, and carbon, plus live grid snapshots and cheapest-window scheduling.

Connects Claude and other MCP clients to myGEKKO building controllers via the official Query API, enabling natural-language queries and control of smart-home devices. It is read-only by default, with write actions available only through explicit opt-in and safety policies.

Description: Data-center, power & gas intelligence MCP server. 33 tools covering 21,000+ data-center facilities (170+ countries), 232 US power markets scored by the DC Hub Power Index (DCPI), 2,000+ tracked M\&A deals, ISO grid telemetry (PJM, ERCOT, CAISO, MISO, SPP, NYISO), fiber routes, energy pricing. License: Free to cite (CC-BY-4.0). Existing distribution: In the official MCP registry; indexe

MCP server for Kardashev Labs US grid data, giving agents live LMP, carbon intensity, load, curtailment, interconnection queues, ERCOT large loads, and the public RT-DA spread forecast track record. Requires no API key.

A Model Context Protocol server providing free financial market data across 13 categories with 83 no-key tools, enabling access to stocks, indices, options, forex, crypto, energy, prediction markets, and more.

Enables querying German distribution grid operator data from vnbdigital.de and BDEW register, including lookup by ID, postcode, coordinates, and free-text search.

Browse and query the U.S. Energy Information Administration API v2 — electricity, petroleum, natural gas, coal, forecasts, and more via MCP. STDIO or Streamable HTTP.

This MCP server provides a single read-only tool to query official CPFL (electric utility) bill download data via a hosted, prepaid service without requiring platform credentials.

An MCP server that wraps the U.S. Energy Information Administration's Open Data API, enabling assistants to fetch live energy data via natural language. It provides tools for querying series, browsing data routes, filtering facets, and running custom queries.

Wraps the US National Renewable Energy Laboratory developer API, enabling access to renewable energy data through an MCP interface.