[{"data":1,"prerenderedAt":161},["ShallowReactive",2],{"example-temperature-correction-en":3,"faq-temperature-correction-en":129,"sources-temperature-correction-en":160},{"input":4,"output":14},{"ambientTempC":5,"irradianceWm2":6,"windSpeedMs":7,"ratedPowerWp":8,"technology":9,"mounting":10,"huldModel":11,"gammaPmpPercentPerC":12,"annualOperatingHours":6,"energyPriceCtPerKwh":13},25,1000,1,440,"c-si","roof","c-si-current",-0.38,30,{"moduleTempC":15,"temperatureRiseK":16,"relativeEfficiency":17,"powerW":18,"powerAtStcTempW":8,"lossPercent":19,"simpleModelPowerW":20,"simpleModelDeviationPercent":21,"mountingComparison":22,"mountingPenaltyKwhPerYear":28,"mountingPenaltyCtPerYear":29,"mountingPenaltyEurPerYear":30,"powerCurve":31,"irradianceWm2":6,"steps":96,"warnings":120},68.10344827586206,43.103448275862064,0.8066171224732461,354.9115338882283,19.338287752675388,367.93103448275866,3.668379117436782,[23,27],{"mounting":24,"moduleTempC":25,"powerW":26},"free",55.21148036253776,379.5040863080841,{"mounting":10,"moduleTempC":15,"powerW":18},24.59255241985579,737.7765725956737,7.377765725956737,[32,36,40,44,48,52,53,56,60,64,68,72,76,80,84,88,92],{"tempC":33,"powerW":34,"simpleW":35},0,493.09700000000004,481.8,{"tempC":37,"powerW":38,"simpleW":39},5,482.25759999999997,473.44000000000005,{"tempC":41,"powerW":42,"simpleW":43},10,471.5282,465.08,{"tempC":45,"powerW":46,"simpleW":47},15,460.9088,456.72,{"tempC":49,"powerW":50,"simpleW":51},20,450.39939999999996,448.35999999999996,{"tempC":5,"powerW":8,"simpleW":8},{"tempC":13,"powerW":54,"simpleW":55},429.7106,431.64,{"tempC":57,"powerW":58,"simpleW":59},35,419.5312,423.28,{"tempC":61,"powerW":62,"simpleW":63},40,409.46180000000004,414.91999999999996,{"tempC":65,"powerW":66,"simpleW":67},45,399.5024,406.56,{"tempC":69,"powerW":70,"simpleW":71},50,389.653,398.2,{"tempC":73,"powerW":74,"simpleW":75},55,379.9136,389.84000000000003,{"tempC":77,"powerW":78,"simpleW":79},60,370.2842,381.48,{"tempC":81,"powerW":82,"simpleW":83},65,360.7648,373.12,{"tempC":85,"powerW":86,"simpleW":87},70,351.35540000000003,364.76,{"tempC":89,"powerW":90,"simpleW":91},75,342.056,356.40000000000003,{"tempC":93,"powerW":94,"simpleW":95},80,332.8666,348.04,[97,102,106,111,115],{"label":98,"expression":99,"value":15,"unit":100,"provenance":101},"moduleTemp","T_a + G \u002F (u0 + u1 * W)","degC","measured",{"label":103,"expression":104,"value":17,"unit":105,"provenance":101},"relativeEfficiency","1 + k1 lnG' + k2 lnG'^2 + k3 T' + k4 T' lnG' + k5 T' lnG'^2 + k6 T'^2","",{"label":107,"expression":108,"value":18,"unit":109,"provenance":110},"modulePower","(G \u002F 1000) * P_STC * eta_rel","W","exact",{"label":112,"expression":113,"value":20,"unit":109,"provenance":114},"simpleModel","P_STC * (G\u002F1000) * (1 + gamma\u002F100 * (T_c - 25))","assumed",{"label":116,"expression":117,"value":118,"unit":119,"provenance":101},"mountingDelta","T_m,roof - T_m,open",12.8919679133243,"K",[121],{"level":122,"code":123,"params":124,"anchors":127},"warning","MOUNTING_HEAT_PENALTY",{"delta":125,"loss":126},12.9,6.5,[128],"mounting",[130,133,136,139,142,145,148,151,154,157],{"q":131,"a":132},"How hot does a solar panel get, and how much power does that cost?","Module temperature follows the Faiman model, T_m = T_a + G \u002F (u₀ + u₁ · W), and power follows the Huld efficiency model at the actual operating point — not the datasheet straight line. The loss is referenced to the power at STC cell temperature rather than the nameplate rating, so it contains only the temperature effect and not losses that simply come from lower irradiance.",{"q":134,"a":135},"How much does the mounting type change module temperature?","It is the most important single figure missing from the datasheet: at 25 °C air, 1000 W\u002Fm² and 1 m\u002Fs wind, the Faiman model gives 55.2 °C free-standing but 68.1 °C roof-mounted or integrated — a 12.9 K difference with identical modules. For panels glued flat onto a van or boat roof this is the most relevant number in the whole yield domain; the calculator prices the penalty in kWh and cents per year.",{"q":137,"a":138},"Over what irradiance range is the calculation valid?","The Huld fit is a regression and holds roughly from 200 W\u002Fm² upwards; below that the calculator warns. Below about 8 W\u002Fm² the fit even extrapolates into negative efficiency — power is clamped to zero there and the range is flagged. Thermal inertia during fast irradiance changes, forced ventilation, partial shading, bifaciality and degradation are not covered.",{"q":140,"a":141},"How large is the difference between mounting types, concretely?","At the reference point (25 °C air, 1000 W\u002Fm², 1 m\u002Fs wind) the Faiman model gives: free-standing 55.2 °C, roof\u002Fglued 68.1 °C — 12.9 kelvin from mounting alone, with identical modules. With c-Si coefficients that is about 6.5% power difference. For camper and boat roofs with glued-on modules this is the single most important number in the whole yield section — the calculator outputs it in kWh and euros per year so you can weigh it against the cost of rear ventilation.",{"q":143,"a":144},"Why does the calculation deviate from the datasheet coefficient?","The datasheet value γ (e.g. −0.38 %\u002F°C) is a straight line that only knows temperature. The Huld model additionally captures the irradiance effect: at low irradiance, efficiency drops even without heat. At 1000 W\u002Fm² both lie close together; at 200 W\u002Fm² they diverge clearly — and the calculator warns when the deviation exceeds 5%. The curve chart shows both models overlaid.",{"q":146,"a":147},"Why is the loss referenced to STC cell temperature instead of rated power?","Because at 600 W\u002Fm² the power is below the rated value anyway — that has nothing to do with temperature. Referencing the loss to rated power attributes irradiance losses to the temperature coefficient. This calculator keeps them separate: the reference is the power at the same irradiance but 25 °C cell temperature. The stated percentage is therefore purely the temperature share.",{"q":149,"a":150},"Do solar panels really work better in cold weather?","Yes — the temperature coefficient works in both directions. On a clear frosty day (−10 °C air, 1000 W\u002Fm², 1 m\u002Fs wind, free-standing) the model gives a module temperature of 20.2 °C: a 440 Wp panel then delivers 450 W, a good 2% above its nameplate rating. On a 30 °C summer day the same irradiance yields only 370 W. Winter still produces less energy overall, because it lacks irradiance — cold improves efficiency, not sunshine. The temperature coefficient is an efficiency argument, not an annual-yield argument.",{"q":152,"a":153},"How much power does a solar panel lose to heat in summer?","On a hot summer day (30 °C air, 1000 W\u002Fm², 1 m\u002Fs wind) the model gives: free-standing 60.2 °C module temperature and 15.9% temperature loss, roof-mounted or glued-on 73.1 °C and 21.5%. At 35 °C air the figures rise to 18.1% and 23.6%. These are operating-point values at the extreme — over a full year the temperature loss is much smaller, because such hours are rare. That is exactly why this calculator evaluates the stated operating point instead of a datasheet flat rate.",{"q":155,"a":156},"Is cooling solar panels worth it?","The most effective “cooling” is not a gadget but rear ventilation: free-standing instead of glued-on lowers module temperature by 12.9 K at the reference point and gains about 25 W on a 440 Wp panel — projected to roughly 25 kWh or €7 per panel per year at 1000 full-load hours. Wind also cools measurably: 5 m\u002Fs instead of 1 m\u002Fs brings a free-standing module from 55.2 down to 42.3 °C (+25 W). Active water or forced cooling is not modelled here; measured against a few euros per panel per year it rarely pays off.",{"q":158,"a":159},"What is NOCT — and why does this calculator use Faiman instead of NOCT?","NOCT (Nominal Operating Cell Temperature, typically 42–46 °C for crystalline silicon) is the module temperature at 800 W\u002Fm², 20 °C air, 1 m\u002Fs wind with an open back. At exactly that point the Faiman model gives 44.2 °C free-standing — consistent with datasheet values. But NOCT knows neither wind speed nor mounting type: a glued-on module already sits at 54.5 °C at the same point. For roof and glued mounting NOCT is therefore systematically optimistic; Faiman uses its own coefficients (u₀, u₁) per mounting type.",[],1786101751595]