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Grasshopper is, in its nature, an innovation project. It aims to make Hydrogen Fuel Cell technology affordable and attractive for potential consumers and markets. So the focus is not on basic science, but rather on the development of reliable and affordable products ready to be introduced in the market. For that objective, the Grasshopper Project presents several technological advances that have been made at many different levels, from individual components to the whole system. The second phase of the project test these developments on the 100kW pilot plant. Allowing for a further optimized design at a greater scale. In order to take the Hydrogen Fuel Cell Power plants to their next level both in functionalities and market accessibility, the pilot plant also aims to demonstrate the flexibility of this technology. Specifically on the electrical market by providing grid support.

These and more features and explained in detail further below, where have divided the plant in three main components for easier understanding:

  • BOP or Balance of Plant, for the handling of fluids, heat and the control of the plat.
  • Fuel Cell modules or Stacks, the heart of the plant where the power is generated.
  • PCS or Power Conversion System, where the raw DC power is converted into ready to use AC Power.

The grasshopper pilot plant is not only a testing environment for the new stacks but also a playground to explore the optimum plant configuration. In order to push the penetration of stationary Hydrogen power plants into the market, several key aspects need to be addressed. Although the main one is of course lowering the price of the system, giving them extra functionalities is also important.

To reduce the Levelized Cost of Energy of a Hydrogen power plant, Grasshopper aims to extend the lifespan of the system and especially the fuel cell stacks to their maximum. A larger lifespan means a more profitable investment. 

What flexibility are you talking about?

Depending on the application, a power plant has different requirements. For example, nuclear or coal-fired power plants work as a “baseload”, meaning they will always produce roughly the same amount of energy no matter how large the demand is. Most of them use non-renewable fuel. On the other hand, “peak” power plants adjust quickly to the demand of the grid. These two combined supply the required power to the grid, and as you can imagine their technology is quite different.

Flexibility in a Hydrogen fuel cell power plant means two different things. First of all, the ability to dynamically change the power output on demand. This allows the use of the technology both as a baseload or peak power plant. On the other hand, flexibility also means a wide range of applications. A dynamic operation opens the door for many different sectors:

  • A portable generator for temporal installations or encampments
  • Emergency generators for critical loads like Data Centers and Hospitals,
  • Electrical Grid services and balancing
  • Combined generation of electricity and heat for industry or housing

The list can go on…

Why a containerised solution?

By keeping the plant inside a container, the plant could be easily fabricated in a different location, transported , and installed in remote location where workforce and/or resources are scarce. This gives the plant a valuable “plug and play” phylosophy, very common in other renewable energy sources like PV.

Check more about it in this dedicated post on our blog. Why containerized Hydrogen Fuel Cell Power Plants make sense?

Is it suitable for cogeneration or CHP?

Absolutely! As it happens with thermal power generators, heat is a byproduct of the chemical reactions inside the Fuel Cell. In this case, since the GH uses PEM technology, the temperature is limited to around 70 ºC. Which makes it especially ideal for low-temperature applications like district heating. Its Heat-to-Power ratio, meaning the amount of heat produced by every electrical power unit, is around 1. Similar to conventional internal combustion engines. This allows for quick deployment into systems already using engines for CHP.

What are the auxiliaries consumption of Fuel Cell Plants

Even when designed as a stand-alone unit and suitable for remote locations, the plant needs some consumables to operate, as it happens with any other power plant. Apart from Hydrogen as fuel, Nitrogen and demineralized water need to be supplied. Nitrogen will be consumed  especially during starts and stops. While demineralized water may only be needed during initial setups or maintenance. In fact, depending on the application, very high-quality DI water can also be a product of the plant to be used in other processes.

Hydrogen PEM Fuel Cells are used in the GH project. These units, frequently called stacks, use Hydrogen as fuel and atmospheric air as comburant to generate electricity. Contrary to heat engines where the fuel is used to generate heat through combustion, and then transforming that thermal energy into movement and/or electricity, fuel cells produce a very controlled REDOX reaction and using the produced voltage and current directly as electric power.  Check out the video on the right for a graphical representation.

What makes GH special is the increased expected lifetime of the stacks. With all the improvements  The increased power density compared to earlier generations of stacks for stationary applications is also a big benefit. With a 300 cm² active area, 100kW can be achieved using only 4 stacks. This is not only an advantage in reducing the Fuel Cell manufacture costs, but also in the rest of the plant, with less piping and easier construction.

What exactly is PEM a Fuel Cell?

Fuel Cells are electrochemical equipment that produce electricity directly from fuel through an oxidation chemical reaction. Compared to other means of power generation like turbines or internal combustion engines, Fuel Cells have no moving parts and DC power is generated ditectly in them. Much like photovoltaic solar panels, they need a DC/AC converter to feed electricity to the grid. Think about them like batteries than can produce power as long as fuel is being injected. Giving them one of the main appeals of heat engines where the maximum energy that can proide is only limited by the size of the tank to store the fuel

PEM is the acronym of “Proton Exchange Membrane” which refers to the technology that allows the reaction between the H2 and O2 inside the fuel cell. Its called Proton Exchange because hydrogen protons travel from the anode side to the cathode where the water is formed.  They operate at low temperature, aproximately 70ºC, and have a very good reaction time, which makes them perfect for applications where the load could change without much prior notice. Check out this great post of Hydrogen Europe which explains the fundamentals and difference between technologies.

https://hydrogeneurope.eu/fuel-cells

Grasshopper aims to provide grid services, therefore PEM fuel cells are the best choice.

What makes the GH Fuel Cell special

This technology has been developed greatly in recent years for mobile applications (like cars, trains boats…), trying to become a sustainable alternative for conventional fossil fuel engines. But the aim of Grasshopper is to apply this technology in stationary applications, meaning its meant to feed power to non-moving facilities like residential buildings in an electrical grid, an industrial complex, or even temporary encampments where a generator is needed.

For these applications, the focus shifts mainly from power density to reduce the cost of electricity. The fuel cell itself is one of the main costs of a Hydrogen power plant. By producing a stack design to last a long time, the initial investment and maintenance costs are reduced. Grasshopper stacks are not only built to last, but they also double the power output with a single unit compared to similar stacks already in the market. Less piping, simpler installation.

As part of the BOP, the electrical system in the Grasshopper pilot plant is designed using commercial components. Available without the need for specific design or manufacturing. The power conditioning system is integrated with grid codes, allowing for direct injection of energy into the grid, or with capabilities to work as an isolated system.

Autonomous system

Grasshopper aims for a product integrated into the “smart grid” philosophy. It includes a bidirectional communication interface with the grid, allowing participation in the electrical market in realtime. It is completely autonomous and therefore needs no operators on-site to generate power apart from the occasional maintenance.

Fast response for Grid balancing

With the penetration of renewable energy sources into the grid, like solar and wind farms, a growing concern for stability appears. DSOs and TSOs need solutions that can increase/decrease power production, restore frequency or respond to the loss of other generators in short periods of time. With an adequate BOP, both electrical and mechanical, Hydrogen Fuel cell power plants can provide this service.

In Europe, several different services can be provided depending on the response time and other characteristics.With the pilot plant, we explore the different products available in the European electricity market. If you want to learn more about it you can check the European Parlament documents here:

https://www.europex.org/eu-legislation/eb-gl/

One connection

The Grasshopper plant uses only a single bidirectional power interface. Meaning there is no need to provide a separate electrical connection for the auxiliaries systems. The plant will already consume part of its produced power to keep electronics, pumps and other equipment running.

Advances towards Blackstart

A blackout refers to a situation when the electrical grid voltage and/or frequency has gone down to very low values. The reasons behind it could be many but often the result is the same, a cascading failure of one generating plant after another. When this happens, restoring the grid from very low voltage can be very tricky. A blackstart system helps exactly with that. Providing the DSO or TSOs with plants with the ability to help restore the grid in case of a blackout is very attractive. We explore the technical requirements to be incorporated in MW scale products.