REST API reference

Base URL https://data.cleantechcontent.co.uk/v1. All endpoints are GET unless stated. The machine-readable version is the OpenAPI 3.1 document.

Tariffs

Endpoint	What it returns	Filters
`/tariffs`	Tariff products with their regional rates nested under `rates`	`region`, `type`, `supplier`, `fuel`, `payment_method`, `include_unverified`, `include_unavailable`, `limit`, `offset`
`/tariffs/{id}`	One tariff by numeric id or slug	`region`
`/tariffs/ev`	EV time-of-use tariffs and EV add-ons	`region`, `supplier`, `include_unverified`
`/tariffs/cap`	Ofgem default tariff cap rows	`region`, `payment_method`, `fuel`, `period` (YYYY-MM-DD), `include_history`

Tariff types: standard_variable, fixed, ev_tou, smart_tou, economy_7, tracker, agile, heat_pump, export, ev_addon, prepayment. Payment methods: direct_debit, standard_credit, prepayment (Octopus tariffs priced the same for every method appear as varying and match a direct debit filter).

curl "https://data.cleantechcontent.co.uk/v1/tariffs?region=C&type=ev_tou"
curl "https://data.cleantechcontent.co.uk/v1/tariffs/octopus-go-fix-12m-26-08-19-electricity?region=M"
curl "https://data.cleantechcontent.co.uk/v1/tariffs/cap?region=N&fuel=gas&payment_method=prepayment"

Rate fields

unit_rate_pence, standing_charge_pence_per_day, off_peak_rate_pence and off_peak_windows, peak_rate_pence and peak_windows, bands (full list for three-band tariffs), export_rate_pence and export_bands for export tariffs, dynamic_summary (7, 30 and 90-day averages) for Agile and Tracker, and provenance: source_url, verified_at, verified_by, confidence, notes.

EV public charging

Endpoint	What it returns	Filters
`/charging/networks`	Networks with operator, pricing page and notes	`include_unverified`
`/charging/prices`	Price rows per network, power band and pricing basis	`network`, `power_band`, `basis`, `include_unverified`, `limit`, `offset`
`/charging/compare`	Cost table for one session, cheapest first	`kwh` (required), `power_band` (required), `basis`

curl "https://data.cleantechcontent.co.uk/v1/charging/compare?kwh=40&power_band=dc_ultra_150kw_plus"

Power bands: ac_slow_7kw, ac_fast_22kw, dc_rapid_50kw, dc_ultra_150kw_plus. Bases: contactless_payg, app_payg, member, subscription. More in the EV charging guide.

Meta (never metered)

Endpoint	What it returns
`/meta/status`	Row counts and newest and oldest `verified_at` per dataset, the cap period in force, recent syncs
`/meta/changelog`	Every insert, update and retirement with old and new values (`limit`, `table`)
`/meta/sources`	Every source URL the data cites, with first and last seen dates
`/meta/enums`	Allowed values for regions, types, bands and bases

Keys and credit

Endpoint	What it does
`POST /keys/free`	Issues a free key (100 calls a day). Body optional: `{ "label", "email" }`
`POST /credits/checkout`	Body `{ "pack": "1200" \| "7000", "email"?, "api_key"? }`. Returns a Stripe Checkout link and a credit key that is topped up when payment completes
`POST /credits/buy?pack=50\|250\|750`	Stripe Machine Payments: returns a 402 challenge; retry with the credential to receive a key holding the pack
`GET /credits/balance`	Remaining calls for the key in `Authorization`

Paying per call

When the free tier is used up you get a 402 Payment Required. That one response carries three ways to continue:

x402: the PAYMENT-REQUIRED header holds the requirement (USD 0.01 in USDC on Base, exact scheme). An x402 client signs a payment and retries with PAYMENT-SIGNATURE; the settled transaction comes back in PAYMENT-RESPONSE.
Stripe Machine Payments: the WWW-Authenticate: Payment header holds an MPP challenge for a 50-call pack (USD 0.50). Retry with the credential; the data comes back together with an X-API-Key-Issued header holding the rest of the pack.
Credit key: buy 1,200 or 7,000 calls with a card on the pricing page and send the key as a bearer token. X-Credit-Balance shows what is left.

# Node example with the official x402 client
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { toClientEvmSigner } from "@x402/evm";
const client = new x402Client();
registerExactEvmScheme(client, { signer: toClientEvmSigner(account) }); // a viem account holding USDC on Base
const paidFetch = wrapFetchWithPayment(fetch, client);
const res = await paidFetch("https://data.cleantechcontent.co.uk/v1/tariffs?region=H&type=ev_tou");