About Chlorine/H2

Using our Proton Exchange Membrane (PEM) fuel cells, Nedstack builds power plants to transform by-product hydrogen from industrial processes into energy. Please find below answers to frequently asked questions about energy recovery from by-product hydrogen.

What is to gain by reusing waste hydrogen?

Chlor-alkali plants are among the main producers of by-product hydrogen. Worldwide, 50 million tons of chlorine is produced annually. If all the hydrogen is converted to electricity, the electricity consumption of the electrolysis plant from the grid is reduced by 20%. Fuel cell conversion of all by-product hydrogen from global chlorine production alone would yield 3000 MW of continuous power. That is equivalent to the electricity consumption of 6 million households.

What are the benefits of waste hydrogen energy recovery?

Summarizing, fuel cell technology brings a lot of benefits to industrial processes with by-product hydrogen. The advantages include:

  • Abundant supply of pure hydrogen at low cost. Using vented hydrogen is even totally free
  • Guaranteed delivery of the generated electricity to the electrolysis factory
  • Savings of up to 20% on the electricity bills, and on CO2 emissions
  • Water generated by the fuel cells can be used in the production process
  • Heat generated by the fuel cells can often be used in the production process.

What is the optimal size of a PEM Power Plant?

Our PEM fuel cell power plants currently range from 75 kW to 2 MW. A larger size of the system leads to lower cost per kWh. Our latest modular PEM fuel cell Power Plant design is suitable for power plants starting from 1 MW.

What is the fuel efficiency of a PEM power plant?

PEM power plants reach an electrical conversion efficiency of around 50%. The system efficiency goes up to 90% if the heat generated in the process is also reused in the plant.

Is it hard to capture waste hydrogen to generate energy?

Nowadays about 15 % of the produced hydrogen is vented to the atmosphere. Capturing instead of venting this hydrogen is a very straightforward process. Fuel cells operating on the vented hydrogen could generate 450 MW of CO2-free power. Capturing the remaining 85% of the hydrogen takes a bit more effort but still is a very low cost option.

What is by-product hydrogen?

Some industrial processes produce hydrogen as by-product. The industrial chemicals chlorine and caustic soda are produced by passing an electric current through a concentrated solution of salt in water. This process is accompanied by the release of hydrogen. This is called by-product hydrogen.The by-product hydrogen can be converted to dc electrical power with PEM fuel cells, which can easily be reused in the process.

What is waste hydrogen?

Some industrial processes produce hydrogen as by-product. The industrial chemicals chlorine and caustic soda are produced by passing an electric current through a concentrated solution of salt in water. This process is accompanied by the release of hydrogen. This is called by-product hydrogen or waste hydrogen. The by-product hydrogen can be converted to electrical power with PEM fuel cells, which can be reused in the process.

Is the chlorine industry the only one to use H2 recovery?

The chlorine and caustic soda industry is the furthest advanced in capturing by-product hydrogen, although there is still a lot of potential remaining. Another industry bound to benefit from hydrogen energy production is the sodium chlorate production. Sodium chlorate is used for the bleaching of pulpwood for paper production. To limit transportation costs, these electrolysis factories are usually located close to saw mills – in remote areas. At these remote locations the by-product hydrogen is often vented as there is no use for it locally. As PEM Power Plants don’t need refuelling, operate under a wide range of climate conditions, and require little maintenance, they are excellently suited to help cut the electricity bills and environmental footprint of sodium chlorate production. Hydrogen produced this sector could generate 300 MW of electricity with fuel cells, again assuming 50% conversion efficiency.

Is the chlorine industry the only one to use H2 recovery?

The chlorine and caustic soda industry is the furthest advanced in capturing by-product hydrogen, although there is still a lot of potential remaining. Another industry bound to benefit from hydrogen energy production is the sodium chlorate production. Sodium chlorate is used for the bleaching of pulpwood for paper production. To limit transportation costs, these electrolysis factories are usually located close to saw mills – in remote areas. At these remote locations the by-product hydrogen is often vented as there is no use for it locally. As PEM Power Plants don’t need refueling, operate under a wide range of climate conditions, and require little maintenance, they are excellently suited to help cut the electricity bills and environmental footprint of sodium chlorate production. Hydrogen produced in this sector could generate 300 MW of electricity with fuel cells, again assuming 50% conversion efficiency.

Is it hard to capture by-product hydrogen to generate energy?

Nowadays about 15% of the produced hydrogen is vented to the atmosphere, while 85% is used as an industrial chemical or is burnt as a fuel in boilers. Capturing vented hydrogen is a very straightforward process. Fuel cells operating on the vented hydrogen could generate 450 MW of CO2-free power.

What are the benefits of by-product hydrogen energy recovery?

Summarizing, fuel cell technology brings a lot of benefits to industrial processes with by-product hydrogen. The advantages include:

  • Abundant supply of pure hydrogen at very low cost. Using vented hydrogen is even totally free
  • Guaranteed delivery of the generated electricity to the electrolysis factory
  • Savings of up to 20% on the electricity bills
  • Water generated by the fuel cells can be used in the production process
  • Heat generated by the fuel cells can often be used in the production process