Steam, Direct Fire or Electric: Choosing Heating

HGMC publishes three heating routes for a brewery: steam, gas direct fire and electric. The decision is rarely about which makes better beer, because all three boil wort; it is about what your building can supply, who will look after the plant, and how much of the brew day you are willing to spend waiting for a ramp. Equipment up to 100 hectolitres is specified around that choice, and the published configurations run from one barrel to a hundred.

What the factory publishes for each route

The published range covers steam-powered, direct-fire and electric brewhouses, with two, three, four and five-vessel configurations that can run either decoction or infusion methods. Heating is listed as electric, steam and gas, and the mash, wort and water flows can be automated with automatic temperature control when the control level is specified up to a fully automatic panel with curve indication and production-record printing.

That structure matters because it separates the heating decision from the automation decision. You can buy a steam system with a PID panel, or an electric system with a fully automatic panel, and the two choices are priced and planned independently. The heating method fixes your building work; the control level fixes your staffing.

Steam: the gentlest heat, the most site work

Steam heats a kettle through a jacket, so the wort never touches a flame or an element and the surface temperature stays far enough above boiling to drive a strong roll without scorching. That even heat is why steam is the usual choice once a plant runs several brews a day, and why a well-designed steam system is often described as the backbone of a larger brewhouse rather than as one option among three.

The cost of that gentleness is infrastructure. A steam installation needs a boiler, a treated water supply, a boiler room or a ventilated space, condensate return, insulation on every pipe, and a maintenance routine with the inspections your jurisdiction requires. Steam also adds a professional to your contact list: somebody has to own the boiler, and in some buildings that is the deciding argument against it.

Direct fire: simple heat with a flue attached

A direct-fired kettle sits over a burner, and the wort is heated through the vessel base. It is the simplest way to boil on a small or medium system, it responds quickly when you change the firing rate, and it needs no boiler and no steam pipework. For gas-fired breweries this is the route that gets a plant running with the least building work and the fewest ancillaries.

What it demands instead is air and exhaust discipline. The burner needs combustion air and a flue, the kettle needs a base designed for the flame pattern to avoid hot spots, and the room needs ventilation sized for the heat it will reject. Kettle bases also age differently from jackets, so inspection of the flame side is part of the routine.

Electric: clean, simple, and decided by your supply

Electric heating removes combustion from the building entirely. There is no flue, no gas connection, no boiler and no flame, which makes it attractive for rented units, upper floors and city sites where a boiler is not permitted. Elements or an immersion heater deliver the energy directly into the wort or into a jacket, and the control panel becomes the only place the heat is managed.

The constraint is electrical. A 2,000 litre kettle ramping to boil in half an hour draws a serious connected load, and if the building's supply cannot deliver it, the answer is a longer ramp rather than a bigger cable. Ask two questions early: how many kilowatts can be supplied to the panel, and what happens to the rest of the building's equipment when the kettle is at full power.

Worked example: sizing a boiler for a 2,000 L kettle

These assumptions are mine and are labelled so you can substitute your own: a 2,000 L kettle, a ramp from 65 to 100 degrees Celsius in 30 minutes, a boil-off of 8 per cent of the kettle volume per hour, a latent heat of about 2,257 kilojoules per kilogram for steam at roughly atmospheric pressure, and no allowance for losses.

Step one, the ramp duty. Heating 2,000 kg of wort by 35 kelvin at about 4.18 kilojoules per kilogram per kelvin is 2,000 multiplied by 4.18 multiplied by 35, or 292,600 kilojoules. Divide by 1,800 seconds and the average power is about 163 kilowatts.

Step two, the boil duty. An 8 per cent boil-off from 2,000 L is 160 L an hour, so about 160 kg of water has to be evaporated every hour: 160 multiplied by 2,257 is 361,120 kilojoules an hour, or roughly 100 kilowatts.

Step three, peak and steady load. During the ramp the kettle needs about 163 plus 100, so around 263 kilowatts; once boiling, the demand falls back to roughly 100 kilowatts. Step four, the steam figure: 263 kilowatts divided by 2,257 kilojoules per kilogram is about 0.12 kg of steam per second, which is roughly 420 kilograms an hour. A boiler rated near 450 kilograms an hour therefore covers that kettle with a margin, and the same arithmetic run with a 60-minute ramp instead of 30 minutes halves the peak and allows a much smaller boiler.

Frequently asked questions

Which heating method is best for a brewery brewhouse?

There is no single best route, because steam, direct fire and electric are all published options. Steam suits plants brewing several times a day and able to house a boiler, direct fire suits small and medium sites without a boiler room, and electric suits rented or city buildings where the supply can carry the load.

Can an electric brewhouse boil a 2,000 litre batch?

Yes, if the electrical supply can carry the connected load, and the practical lever is ramp time: a longer ramp needs fewer kilowatts. Published brewhouses can be specified with electric heating in two, three, four or five-vessel configurations, with control from a PID panel up to a fully automatic PLC panel.

Match the heat to the building

Write down three things before you choose: what services the building can supply, whether anyone on site can own a boiler or a gas burner, and how long a ramp and a boil are allowed to take on your busiest day. Those three answers usually eliminate one option immediately, and the published Brewhouse equipment pages show which vessel configurations are available once the choice is made.

It also helps to see the whole plant rather than the kettle alone, which is what the HGMC site sets out, including fermentation tanks and bright tanks that have to be cooled whatever heats the wort. For the equipment list that sits downstream of the boil, the beer brewing equipment pages cover the rest of the line. Decide the heat source early, because it changes the floor plan more than any other single choice.

Published heating options, vessel configurations, control levels and the 6-year warranty on tank accessories and electronic components against manufacturing defects come from the manufacturer's own website, read 23 Sept 2026; the boiler and power figures above are my own arithmetic from the stated assumptions.^[1] Delivery runs from deposit to door delivery in 90 to 150 days depending on the order.