export function estimateSystemSize({monthly_kwh,peak_sun=5,panel_w=400,derate=0.8}){
    const daily_kwh = monthly_kwh/30;
    const required_kw = daily_kwh / peak_sun / derate;
    const panels = Math.ceil((required_kw*1000)/panel_w);
    return {required_kw: Number(required_kw.toFixed(3)), panels};
}
