# Saylor Innovations Solar Payback Calculator

> Saylor Innovations Solar Payback Calculator is a paid API for AI agents from saylorinnovations.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-30).

Calculates solar panel payback period in years, ROI, IRR, and lifetime savings given system size, cost, electricity rate, and optional incentives

## Facts

- Endpoint: GET https://saylorinnovations.com/api/solar/payback?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/saylor-innovations-solar-payback-calculator-0661ba63
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_67iIfwOmPVFtMNHq5yx10

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability saylor-innovations-solar-payback-calculator-0661ba63
```

Example prompt: How long will it take for a 8kW solar system to pay for itself if the installed cost is $2.90 per watt, my electricity rate is $0.14 per kWh, and I qualify for the 30% federal tax credit?

## When to prefer this

Choose this endpoint when you need a detailed, year-by-year solar financial model including IRR and degradation-adjusted production, especially when the user provides system size, cost, and electricity rate. Prefer over simple payback calculators when rate escalation, panel degradation, maintenance costs, and incentive modeling are needed in a single call.

## Known failure modes

- Missing required parameters (system_kw, cost_per_watt, electricity_rate) return validation error
- Negative or zero values for cost or system size may produce nonsensical results
- Very low electricity rates may yield no positive payback within system lifetime, returning null for irr_percent
- Extreme input combinations (e.g. 0.001 kWh rate) may produce null or unrealistic IRR values

## How this service works

Solar panel payback in years, ROI, IRR and lifetime savings from system size and cost, with rate escalation, degradation, incentives and maintenance.

## Output

Returns a JSON object with payback_years, roi_percent, irr_percent, net_profit_over_period, system_cost, net_cost after incentives, year_one_kwh production, and a year-by-year milestones array showing cumulative savings and production. Also includes a plain-language note and source attribution.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "system_kw",
      "cost_per_watt",
      "electricity_rate"
     ],
     "properties": {
      "system_kw": {
       "type": "string",
       "description": "system size in kW"
      },
      "cost_per_watt": {
       "type": "string",
       "description": "installed price per watt (or give system_cost)"
      },
      "electricity_rate": {
       "type": "string",
       "description": "retail price per kWh"
      },
      "incentive_percent": {
       "type": "string",
       "description": "optional tax credit or rebate percent"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "json"
    },
    "example": {
     "type": "object",
     "required": [
      "payback_years",
      "net_profit_over_period"
     ],
     "properties": {
      "note": {
       "type": "string",
       "description": "Plain-language caveat about how to read and use the result"
      },
      "source": {
       "type": "string",
       "description": "Where the data or formula comes from"
      },
      "net_cost": {
       "type": "number",
       "description": "Cost after incentives"
      },
      "system_kw": {
       "type": "number",
       "description": "System size"
      },
      "milestones": {
       "type": "array",
       "items": {
        "type": "object",
        "properties": {
         "kwh": {
          "type": [
           "number",
           "null"
          ],
          "description": "Production that year"
         },
         "year": {
          "type": [
           "number",
           "null"
          ],
          "description": "Year number"
         },
         "savings": {
          "type": [
           "number",
           "null"
          ],
          "description": "Savings that year"
         },
         "cumulative_net": {
          "type": [
           "number",
           "null"
          ],
          "description": "Cumulative position after that year"

… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/saylor-innovations-solar-payback-calculator-0661ba63/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from saylorinnovations.com](https://www.zero.xyz/host/saylorinnovations.com/llms.txt)