This special interest group is for professionals to connect and discuss all types of carbon-free power alternatives, including nuclear, renewable, tidal and more.

Post

A Hydrogen-based Microgrid where Electrolyzer Hydrogen is replaced by Hydrogen from Alternative Sources (Methanol-Reformation)

image credit: https://www.hydrogenfuelnews.com
Sandeep Chandra's picture
Director Hydrozen2050

Founder & Managing Director, HYDROZEN2050, finding ways to make Renewable Hydrogen accessible and affordable. After successful prototypes now working on commercialization of on-site...

  • Member since 2021
  • 25 items added with 2,792 views
  • Sep 21, 2022
  • 165 views

Abstract

Key desirables when planning for a microgrid, including a microgrid that is hydrogen-based are - to achieve the right balance in demand and supply, to achieve higher energy efficiency and to have reliability and resiliency.

Problem

When the primary generator of energy in a microgrid is Solar or Wind, the very nature of such generators characterized by load transients, switch on/switch off events and idling conditions [1], makes it challenging even for a PEM Electrolyzer (the most popular electrolyzer type due to its durability) to perform optimally. A PEM Electrolyzer performs better than Alkaline Electrolyzers under dynamic conditions but it must still be accompanied by a power conditioning system if its performance is not to be compromised by inherently occurring transients that can lead to failures with the downstream Fuel Cell. A power conditioning system for this can be complex, cumbersome and costly.

The problem can be alleviated by augmenting with an intermediate Hydrogen-storage system which will add further costs to the end-to-end system

Our Solution

Designing a microgrid ab initio, we at Hydrozen2050, use a completely different approach for setup of a hydrogen-based microgrid.

We recommend a Fuel Cell supplied with a constant and smooth stream of renewable Hydrogen, that is produced by our Methanol-Reformer system, then compressed and fed directly into the Fuel Cell.

Since in our system Hydrogen [2] is produced constantly with a smooth flow rate, the integration with the downstream Fuel Cell reduces to a simple hydrogen pressure control system. This is in stark contrast to a strongly coupled subsystem, with high nonlinearity and complex dynamic processes, required to mitigate the variability of power fed to a PEM Electrolyzer. Even then, a hydrogen pressure control system is still required to deliver the electrolyzer-produced hydrogen to the Fuel Cell

So, in comparison, our system is significantly less complex, less cumbersome and much cheaper

Details

Regardless of the source of hydrogen that feeds the Fuel Cell – whether the source is a PEM Electrolyzer or a Methanol-Reformer - in both cases, hydrogen pressure control system is still required.

It is important to point out here that in our case the Methanol-Reformer is a completely external and independent system to the Fuel Cell. It is known that the cost of the reformate within the Fuel Cell is a significant factor contributing to higher cost (~30% of the total system unit manufacturing and service cost of a Fuel Cell) [3], a cost which we avoid completely.

The purpose of this hydrogen pressure control system (and air/oxygen inlet pressure system) is crucial to ensure that the inlet pressure be carefully maintained within the designed operating range [4]. This applies regardless of whether the Fuel Cell is a low-pressure or high-pressure Fuel Cell. Whereas a high-pressure Fuel Cell is desirable when higher power density is desirable (eg in an FCEV), low-pressure Fuel Cell comes with a benefit that less sealing, lower probability of membrane fracture and lower parasitic losses are observed [5] (eg benefits for stationary applications).

Conclusion

To gain the benefits of clean and reliable power, the planning of a microgrid invariably includes a Fuel Cell. A Fuel Cell offers reliable generation as it can run continuously 24 hours a day, seven days a week, 365 days a year (as long it has a fuel – Hydrogen - supply). Providing a constant supply of renewable Hydrogen is not practically possible with a variable energy source like Solar or Wind but with a Methanol-Reformer it certainly is.

References

Sandeep Chandra's picture
Thank Sandeep for the Post!
Energy Central contributors share their experience and insights for the benefit of other Members (like you). Please show them your appreciation by leaving a comment, 'liking' this post, or following this Member.
More posts from this member
Discussions
Spell checking: Press the CTRL or COMMAND key then click on the underlined misspelled word.
Matt Chester's picture
Matt Chester on Sep 21, 2022

Across the country and even across the globe, different regions and different grids have unique opportunities available to them-- by natural resources, by geography, by customer profile, etc. I'm curious if there are any particular characteristics a region should look at to determine if they are optimal for this type of hydrogen-based microgrid or if there are any where it may be less feasible or less economic?

Thanks Sandeep!

Sandeep Chandra's picture
Sandeep Chandra on Sep 22, 2022

The main input for the Methanol Reformer (M-R) to produce Renewable Hydrogen is Methanol. If this Methanol is renewable, eg. e-Methanol or Bio-Methanol, then resulting Hydrogen is renewable. Even if Methanol is the common Methanol (fossil-fuel based), then also we can easily capture the by-product CO2 (ie CCU/S) and the resulting Hydrogen will be carbon-negative. We have a separation unit integrated within the M-R, so any by-products are easily separable to leave high purity Hydrogen (>99.9%). So, depending upon the geography, availability of renewable Methanol will be an important factor in deciding whether to site M-R based Hydrogen production plant there. In regional areas, eg. a cattle station in remote Australia, or a dairy farm in mid-West, US or a sugarcane plantation in India/Brazil, places where biomass is abundant, expectation of e-Methanol/Bio-Methanol is high and M-R plant can be sited in the vicinity. But given our small footprint, fast production rate of hydrogen, use of very cheap materials as catalysts, overall resulting in on-site, on-demand hydrogen production, we have a business case to site it in metro areas, service stations, residential complexes, etc to make hydrogen to feed fuel cells to produce power

Get Published - Build a Following

The Energy Central Power Industry Network is based on one core idea - power industry professionals helping each other and advancing the industry by sharing and learning from each other.

If you have an experience or insight to share or have learned something from a conference or seminar, your peers and colleagues on Energy Central want to hear about it. It's also easy to share a link to an article you've liked or an industry resource that you think would be helpful.

                 Learn more about posting on Energy Central »