# nrel_pvwatts

Estimate solar PV system production using NREL's PVWatts v8 model. Returns annual and monthly AC energy output (kWh), solar resource (kWh/m²/day), and capacity factor. Used by solar developers, homeowners, and ESG analysts to size and estimate solar arrays.

Agent View of the PolicyLayer registry record for `nrel_pvwatts`. HTML page: https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/nrel-pvwatts

## Facts

- Tool: `nrel_pvwatts`
- Server: Livedatalink (`https://livedatalink.ai/mcp`) — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink.md
- Homepage: https://github.com/blackboxfoundry/livedatalink
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server auth posture: open
- Server CORS policy: *
- Server rate-limited: no
- Parameters: 9 (1 required)
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `lat` | number | no | Latitude in decimal degrees. Use with lon as alternative to address. |
| `lon` | number | no | Longitude in decimal degrees. Use with lat as alternative to address. |
| `tilt` | number | no | Array tilt angle in degrees (default 20). |
| `losses` | number | no | Total system losses percent (default 14). |
| `address` | string | no | Street address, city/state, or place name. Either address OR lat+lon required. |
| `azimuth` | number | no | Array azimuth in degrees (default 180 = south for northern hemisphere). |
| `array_type` | number | no | 0=fixed open rack, 1=fixed roof (default), 2=1-axis tracking, 3=1-axis backtracking, 4=2-axis tracking. |
| `module_type` | number | no | 0=standard (default), 1=premium, 2=thin film. |
| `system_capacity` | number | yes | System size in kilowatts DC (e.g. 5 for a 5 kW residential system). |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "nrel_pvwatts",
    "arguments": {
      "system_capacity": 0
    }
  }
}
```

## Why nrel_pvwatts is rated Low

This tool queries the NREL PVWatts model to retrieve solar production estimates. It is purely informational—reading from a calculation service and returning results to the user. No side effects, state changes, or irreversible actions occur. Appropriate for Read category with low severity since misuse would merely produce incorrect solar estimates, not compromise systems or finances.

From the tool's own definition: "Tool 'returns' energy production estimates and solar resource data without modifying any external systems or data. Verbs indicate retrieval: 'Estimate' and 'Returns' output data."

## Use case

AI agents call nrel_pvwatts to retrieve information from Livedatalink without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Livedatalink:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "nrel_pvwatts": {}
  }
}
```

## Other tools on Livedatalink (279)

- `beneficial_owner_screen` — Destructive — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/beneficial-owner-screen.md
- `cdc_dataset_query` — Execute — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/cdc-dataset-query.md
- `clinical_site_selector` — Execute — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/clinical-site-selector.md
- `air_quality` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/air-quality.md
- `bank_health_report` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/bank-health-report.md
- `bls_indicator` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/bls-indicator.md
- `bls_series` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/bls-series.md
- `book_details` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/book-details.md
- `book_fulltext_search` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/book-fulltext-search.md
- `book_get_text` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/book-get-text.md
- `book_search` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/book-search.md
- `book_status` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/book-status.md
- `bounce_scanner` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/bounce-scanner.md
- `candlestick_signals` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/candlestick-signals.md
- `cargo_crate` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/cargo-crate.md
- `carrier_vetting_score` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/carrier-vetting-score.md
- `caselaw_case_details` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/caselaw-case-details.md
- `caselaw_citation_lookup` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/caselaw-citation-lookup.md
- `caselaw_opinion_text` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/caselaw-opinion-text.md
- `caselaw_search` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/caselaw-search.md
- `cdc_drug_overdose_deaths` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/cdc-drug-overdose-deaths.md
- `cdc_excess_deaths_covid` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/cdc-excess-deaths-covid.md
- `cdc_flu_surveillance` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/cdc-flu-surveillance.md
- `cdc_leading_causes_of_death` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/cdc-leading-causes-of-death.md
- `cdc_outbreak_reports` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/cdc-outbreak-reports.md
- `cdc_vaccination_coverage` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/cdc-vaccination-coverage.md
- `cdc_weekly_deaths_by_state` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/cdc-weekly-deaths-by-state.md
- `census_business` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/census-business.md
- `census_commute_employment` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/census-commute-employment.md
- `census_demographics` — Read — https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink/census-demographics.md
- …and 249 more: https://policylayer.com/tools/io-github-blackboxfoundry-livedatalink.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=io-github-blackboxfoundry-livedatalink · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-blackboxfoundry-livedatalink