Data studies on Hungary's power system and plain-language explainers on solar PV and wind, by Atilla Bijen Jalili.https://atillabijenjalili.com/en-gbSat, 10 Oct 2026 00:00:00 GMThttps://atillabijenjalili.com/research/bifacial-gain-albedo/https://atillabijenjalili.com/research/bifacial-gain-albedo/Bifacial gain over grass on trackers was about 5% to 9% in field test arrays. Albedo, bifaciality factor and row geometry decide it. Includes a Hungarian view.Sat, 10 Oct 2026 00:00:00 GMTExplainerPV performancebifacial modulesalbedobifaciality factorIEC TS 60904-1-2single-axis trackersgrassland solar parkscontact@bijenjalili.com (Atilla Bijen Jalili)https://atillabijenjalili.com/research/capacity-factor-vs-performance-ratio/https://atillabijenjalili.com/research/capacity-factor-vs-performance-ratio/Capacity factor vs performance ratio: output against rated capacity, and against the sunlight received. A Szolnok example gives 14.3% (DC basis) and 78.75%.Sat, 10 Oct 2026 00:00:00 GMTExplainerPV performanceperformance ratiocapacity factorIEC 61724-1PVGISDC/AC ratioHungarycontact@bijenjalili.com (Atilla Bijen Jalili)https://atillabijenjalili.com/research/grid-inertia-grid-forming-inverters/https://atillabijenjalili.com/research/grid-inertia-grid-forming-inverters/Grid inertia is stored rotational energy that slows frequency changes. Solar and batteries add none by default; grid-forming inverters can emulate some of it.Sat, 10 Oct 2026 00:00:00 GMTExplainerGrid and systemgrid inertiagrid-forming inverterRoCoFsynthetic inertiaENTSO-ENC RfGcontact@bijenjalili.com (Atilla Bijen Jalili)https://atillabijenjalili.com/research/hungary-duck-curve-residual-load/https://atillabijenjalili.com/research/hungary-duck-curve-residual-load/On April to September days, midday residual load fell from 3,958 MW in 2020 to 843 MW in 2026, so the evening ramp of the Hungary duck curve grew to 4,430 MW.Sat, 10 Oct 2026 00:00:00 GMTData studySolar outputduck curveresidual loadnet loadsolar sharePaksENTSO-EHungarycontact@bijenjalili.com (Atilla Bijen Jalili)https://atillabijenjalili.com/research/hungary-electricity-imports-by-hour/https://atillabijenjalili.com/research/hungary-electricity-imports-by-hour/Hungary electricity imports turned into net exports at April to September middays from 2023, while evening and night imports rose.Sat, 10 Oct 2026 00:00:00 GMTData studyGrid and systemelectricity importsnet exportscross-border tradeinterconnectorssolarHungarycontact@bijenjalili.com (Atilla Bijen Jalili)https://atillabijenjalili.com/research/hungary-negative-quarter-hours-2025-2026/https://atillabijenjalili.com/research/hungary-negative-quarter-hours-2025-2026/Negative electricity prices in Hungary came in 894 day-ahead quarter-hours in the first year of 15-minute trading, 88.9% of them between 10:00 and 16:00.Sat, 10 Oct 2026 00:00:00 GMTData studyPower pricesnegative pricesday-ahead marketHUPX15-minute MTUSDACsolarresidual loadHungarycontact@bijenjalili.com (Atilla Bijen Jalili)https://atillabijenjalili.com/research/hungary-solar-capacity-figures-explained/https://atillabijenjalili.com/research/hungary-solar-capacity-figures-explained/Published figures for Hungary solar capacity run from 7.55 to 10.2 GW because they differ in unit, plant types and date. This guide shows what each source counts.Sat, 10 Oct 2026 00:00:00 GMTExplainerSolar outputsolar capacityMAVIRHMKEAC vs DCENTSO-EIRENASolarPower EuropeNECPHungarycontact@bijenjalili.com (Atilla Bijen Jalili)https://atillabijenjalili.com/research/hungary-wind-solar-complementarity/https://atillabijenjalili.com/research/hungary-wind-solar-complementarity/Wind solar complementarity in Hungary is mostly seasonal: the monthly output correlation is -0.41, but only -0.15 once the seasonal cycle is removed (2020 to 2025).Sat, 10 Oct 2026 00:00:00 GMTData studyWind and hybridswind solar complementarityseasonal cyclecapacity factorseasonal outputHungaryEnergy-Chartscontact@bijenjalili.com (Atilla Bijen Jalili)https://atillabijenjalili.com/tools/lcoe-calculator/https://atillabijenjalili.com/tools/lcoe-calculator/Solar LCOE calculator with the formula, benchmarked starting inputs and a Szolnok example: EUR 52/MWh at EUR 700/kWp, a 5% real discount rate and 30 years.Sat, 10 Oct 2026 00:00:00 GMTCalculatorProject economicsLCOEsolar PVdiscount ratePVGISproject economicsHungarycontact@bijenjalili.com (Atilla Bijen Jalili)https://atillabijenjalili.com/tools/pv-degradation-calculator/https://atillabijenjalili.com/tools/pv-degradation-calculator/Solar panel degradation calculator: 1% in the first year and 0.4% a year leaves 87.4% at year 30. Set your own rates to see lifetime energy and the 80% point.Sat, 10 Oct 2026 00:00:00 GMTCalculatorPV performancePV degradationperformance loss rateLIDLeTIDUVIDmodule warrantycontact@bijenjalili.com (Atilla Bijen Jalili)https://atillabijenjalili.com/research/pv-hail-testing-iec-61215-vs-kiwa-hss/https://atillabijenjalili.com/research/pv-hail-testing-iec-61215-vs-kiwa-hss/The IEC 61215 hail test fires 11 ice balls of 25 mm at 23.0 m/s, about 2 J each. Kiwa PVEL and RETC test 35 to 60 mm hail. What each result proves.Sat, 10 Oct 2026 00:00:00 GMTExplainerPV performancehailIEC 61215Kiwa PVELRETCmodule reliabilityhail stowinsurancecontact@bijenjalili.com (Atilla Bijen Jalili)https://atillabijenjalili.com/tools/pv-temperature-loss-calculator/https://atillabijenjalili.com/tools/pv-temperature-loss-calculator/Solar panel temperature coefficient calculator: at 42 °C air, 1,000 W/m² and 1 m/s, a -0.29 %/°C module reaches 74.3 °C and loses 14.3% of its power.Sat, 10 Oct 2026 00:00:00 GMTCalculatorPV performancetemperature coefficientcell temperatureSAPMpvlibNMOTPV heat losscontact@bijenjalili.com (Atilla Bijen Jalili)https://atillabijenjalili.com/research/single-axis-trackers-vs-fixed-tilt/https://atillabijenjalili.com/research/single-axis-trackers-vs-fixed-tilt/Single-axis tracker vs fixed tilt: PVGIS gives 16.2% more energy at Szolnok, Hungary; metered field results show about 12.8% to 15%. US cost data and trade-offs.Sat, 10 Oct 2026 00:00:00 GMTExplainerPV performancesingle-axis trackerfixed tiltPVGISbifacialenergy yieldHungarycontact@bijenjalili.com (Atilla Bijen Jalili)