Globalization in ASP.NET cloud applications

DateTimeExtensions.cs

using System;

namespace Auction.Web.Utility
{
    public static class DateTimeExtensions
    {
        public static DateTime ToLocalAuctionTime(this DateTime dt)
        {
            // dt.DateTimeKind should be Utc!
            var tzi = TimeZoneInfo.FindSystemTimeZoneById(AppSettings.TimeZoneId);
            return TimeZoneInfo.ConvertTimeFromUtc(DateTime.SpecifyKind(dt, DateTimeKind.Utc), tzi);
        }

        public static DateTime ToUtcTime(this DateTime dt)
        {
            var tzi = TimeZoneInfo.FindSystemTimeZoneById(AppSettings.TimeZoneId);
            return TimeZoneInfo.ConvertTimeToUtc(dt, tzi);
        }

        public static DateTime RoundDown(this DateTime dateTime, int minutes)
        {
            return new DateTime(dateTime.Year, dateTime.Month,
                 dateTime.Day, dateTime.Hour, (dateTime.Minute / minutes) * minutes, 0);
        }
    }
}

GetActiveAuction.cs

    public class GetActiveAuction : Query<Auction>
    {
        public override Auction Execute(DbAccess context)
        {
            return context.Query<Auction>("SELECT * FROM Auction WHERE State = @State AND [Start] <= @Now AND [End] >= @Now", new { State = AuctionState.Running, Now = DateTime.UtcNow }).FirstOrDefault();
        }
    }

web.config

  <appSettings>
    <add key="TimeZoneId" value="W. Europe Standard Time" />
  </appSettings>
  <system.web>
    <globalization culture="nl-NL" uiCulture="nl-NL" enableClientBasedCulture="false" requestEncoding="utf-8" responseEncoding="utf-8" />
  </system.web>