Surplus buying and selling
Electric Boilers Suddenly in Vogue Again
With zero emissions, economical electric steam and hot water boilers deliver maximum thermal output in minimum spatial footprint By: Del Williams
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or EU and U.S. industry, process heating and steam production are significant sources of energy use, and at many industrial sites boilers can account for up to 60% of energy costs. Process heating is usually from steam, which is used to increase the temperature in a process vessel. Due to the threat of global warming as well as international commitments to the Paris Accord on Climate Change, industrial processors in Europe and North America are tasked with significantly reducing their environmental footprint in record time. In response, last year the 27-nation European Union (EU) agreed to cut greenhouse gas carbon emissions by 55% by 2030 compared to 1990 levels. According to a recent report that has tracked the EU's power sector since 2015, renewables surpassed fossil fuels last year (38% to 37%), indicating that industry is already pivoting away from carbon emissions. Even the U.S., which recently rejoined the Paris Agreement, has targets for American businesses to achieve a carbon pollution-free power sector by 2035 and a net-zero economy by 2050. While the interest of industry in electric boilers for process heating and steam production has waxed and waned in the last century, suddenly it is in vogue again. Whether to honor Environmental Social and Governance (ESG) goals, meet regulatory commitments, or take advantage of government credits and incentives, a growing number of industrial facilities are installing new or retrofit high-voltage electrode boilers that are compact, economical, and produce no emissions. This is, in part, due to technological advances in electric boiler design that increase the output to a level that rivals even large gas or oil-fired boilers. When process heating is used to raise process vessel temperature, electric-powered alternatives are sure to be a critical piece of the puzzle in meeting future emission reduction goals.
Transitioning from High-Emission Gas and Oil-Fired Boilers In industrial processing, besides the notorious greenhouse gasses carbon dioxide (CO2) and methane (CH4), natural gas-fired boilers and furnaces emit dangerous nitrogen oxides (NOx), carbon monoxide (CO), and nitrous oxide (N2O), as well as volatile organic compounds (VOCs), sulfur dioxide (SO2), and particulate matter (PM).
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However, many industrial process engineers familiar with gas-fired boilers mistakenly believe that electric boilers cannot match the output of the traditional, fossil fuel burning units. Due to considerable advances in electric boiler technology, that is far from the case. Today, such technology can match the capacity of large gas or oil-fired boilers in a much smaller footprint. Electric boilers utilize the conductive and resistive properties of water to carry electric current and generate steam. An A.C. current flows from an electrode of one phase to ground using the water as a conductor. Since chemicals in the water provide conductivity, the current flow generates heat directly in the water itself. The more current (amps) that flows, the more heat (BTUs) is generated, and the more steam produced. Crucially, almost 100% of the electrical energy is converted into heat with no stack or heat transfer losses. As an example, the electrodes of the CEJS High Voltage Electrode Steam Boiler by Acme, a Canada-based manufacturer of industrial and commercial boilers, are vertically mounted around the inside of the pressure vessel. This enables the unit to produce maximum amounts of steam in a minimum amount of floor space, with boiler capacity from 6MW to 52MW. The boiler operates at existing distribution voltages, 4.16 to 25 KV with up to 99.9% efficiency, and can produce up to 170,000 pounds of steam per hour. With pressure ratings from 105 psig to 500 psig, the boilers are designed to ASME Section 1, and are certified, registered pressure vessels at the location of the boiler. “There is an entire generation of industrial process engineers that grew up with oil and gas-fired boilers almost
