One exception to note: If the food's sitting in an environment where the temperature is over 90Â°F, the USDA says the food should only be left out for one hour, so keep an eye on the clock if you're serving food on a hot day!
Estimated cost of hydrogen per kilogram in a variety of scenarios. With all of this in mind, here are the cost estimates per kilogram (which each include $1.25 for taxes): Hydrogen from natural gas (produced via steam reforming at fueling station). $4 â $5 per kilogram of hydrogen.
Using values from the tables, calculate the fuel cost of producing steam. Steam Cost = ($8.00/MMBtu/10 6 Btu/MMBtu)â¯xâ¯1,000â¯lbxâ¯1,006â¯(Btu/lb)/0.857 = $9.39/1,000 lb Effective Cost of Steam The effective cost of steam depends on the path it follows from the boiler to the point of use.