are steam boilers efficient

steam boilers efficient

The most important factor that determines how efficient a steam boiler is is its fuel-to-steam efficiency. This efficiency measure reflects the amount of chemical energy in the fuel that is converted to heat energy in steam going to the turbines. Other important factors include combustor efficiency, stack gas temperature and unburned carbon losses. The first two are directly related to the combustion technology while the last is a function of how well the combustion system is controlled.

The largest component of a boiler’s efficiency loss is sensible heat lost with the flue gases. This loss is dependent on the stack gas temperature, excess air and burnout. The exhaust temperature is determined mainly by the type of combustible fuel used, while the excess air and burnout depend on the combustion technology. Insufficient excess air leads to unburned combustibles and a high carbon content in the residue while too much results in a lower combustion efficiency and a higher stack gas temperature.

Besides the stack gas temperature, other important factors in measuring a Efficient Steam Boiler are dry gas loss, water-from-fuel loss and blowdown. The first two are mainly affected by the combustion technology, while the latter is more a function of the overall system design and operation.

are steam boilers efficient

Another major factor in determining a boiler’s efficiency is the ability to achieve a high turndown. A high turndown allows the boiler to supply steam at a range of rates without shutting down and restarting which reduces wear and tear on the equipment. It also improves the energy efficiency by using less fuel to run at lower loads.

In addition to fuel-to-steam efficiency, a boiler’s efficiency is also influenced by its own power consumption, which is the energy required to operate and pump the feedwater into the boiler to produce steam. This energy is included in the total heat loss, which is reflected in the AFUE calculation.

It is also important to remember that the AFUE calculation only measures a boiler’s efficiency at one point in time, under a fixed condition, at full load. In real life, the boiler usage changes as demand rises and falls. In these circumstances, operational efficiency is a better indicator of how efficiently the boiler will perform in actual use.

A high efficiency steam boiler can significantly reduce a facility’s energy consumption and its associated costs. The initial investment in a new high efficiency system can often be recovered in the first year alone through fuel savings, and the savings will continue to accrue year-after-year.

The team at Hargett can help you find the right high efficiency steam boiler for your facility. Contact us today to learn more. Our Miura experts are here to assist you. We can help you make an informed purchase decision that will allow your facility to maximize its efficiency and minimize its operating costs. We can even arrange for financing to make your purchase more manageable.