300 ft of 1/2" poly is about 12.5 sq-ft of solar collection area. In your area, the maximum solar radiance on a flat plane is about 2634 BTU/sqft/day. At that flow rate, the panel should be about 80% efficient so the maximum BTU the panel could possible produce is about 26340 BTUs. Assuming the pool is about 5500 gallons, that would add only 0.57 degrees to the pool.

Exit temperature of the panel is not all that relevant without taking into account the flow rate and inlet temperature. What is important is the number of BTUs added to the pool each day and then the amount of those BTUs that is lost each day.

But I think your flow rate is much lower than what you think it is. The maximum heat gain at solar noon would be only 5F at that flow rate for that size panel. To get that high of an exit temperature, flow rate would need to be much lower.

Pool Parameters | Scenario1 |

Pool Volume (g) | 5500 |

Panel Size (sqft) | 12.5 |

Panel Flow Rate (GPM) | 1.25 |

Panel Efficiency | 80% |

| |

Solar Input | |

Solar Daily (BTU/sqft/day) | 2634 |

Solar Peak (BTU/sqft/Hr) | 315 |

| |

Calculations | |

Total Pool Heat Gain (BTU) | 26340 |

Pool Temperature Rise (F) - Without Heat Loss | 0.57 |

Peak Hour Panel Output (BTU/min) | 53 |

Peak Hour Panel Inlet to Outlet Heat Gain (dF) | 5 |