In this study, power-to-gas, whereby hydrogen is generated electrolytically, and power-to-power, whereby electricity is used to produce hydrogen which is used, in turn, to generate electricity at a later time, are examined for their efficiency and emissions reductions in providing energy storage and ancillary services. Due to a large baseload of nuclear energy in the province of Ontario, and with wind generation added to the grid prior to 2014, the supply of electricity exceeds demand at certain times of the year during off-peak hours. To manage this excess supply, electricity is exported to neighboring provinces and states at a low, often negative price, due to the decreased demand and surplus generation. To curb these exports, the Independent Electricity System Operator (IESO) has switched renewable generators from nondispatchable to dispatchable energy sources that can be turned on or off or adjusted to output a different quantity of energy. In addition, due to the large baseload, the IESO has also shifted to allowing loads to offer demand response services previously only offered by generators. In this analysis, the rapid response of polymer electrolyte membrane electrolyzers, used to generate hydrogen in power-to-gas and power-to-power systems is also able to offer important and high value auxiliary and regulatory power services. In power-to-gas systems, the hydrogen produced is an alternative energy vector which can be contained within the natural gas infrastructure or other storage medium. For this analysis, the authors employ the General Algebraic Modeling Simulation to develop a simulation of a 2-MW power-to-gas and power-to-power system that produces hydrogen for energy storage and then uses this hydrogen to generate electricity when there is a peak in energy demand. This energy is then reintroduced into the electrical grid using a hydrogen turbine. The power-to-power scheme, although typically less energy efficient, provides the flexibility to meet changing energy demands while generating hydrogen that can be used for industrial purposes and as a transportation fuel.

Chapter Contents:

• Abstract
• 11.1 Introduction
• 11.2 Methodology
• 11.2.1 Mixed integer linear programming formulation
• 11.3 Results and discussion
• 11.3.1 Development of a premium price mechanism for the energy hub
• 11.4 Conclusion
• References

Inspec keywords: power markets; power generation economics; fuel cell power plants; power generation dispatch; hydrogen storage; demand side management; pricing; proton exchange membrane fuel cells; hydrogen production

Other keywords: wind generation; transportation fuel; general algebraic modeling simulation; power-to-gas system; nuclear energy; IESO; electrical grid; emission reductions; hydrogen production; nondispatchable energy sources; energy storage; switched renewable generators; surplus generation; alternative energy vector; ancillary services; power-to-power system; natural gas infrastructure; dispatchable energy sources; Independent Electricity System Operator; electricity generation; hydrogen turbine; power 2 MW; urban areas; Ontario; regulatory power services; polymer electrolyte membrane electrolyzers; negative price; demand response services

Subjects: Fuel cell power plants; Other energy storage; Power system management, operation and economics