Energy Density Illustration

Maritime Energy Density

At the core of energy transition in the Maritime industry is a physics problem, namely Energy Density


What is Energy Density?

Energy Density can be measured in two ways:

 Volume: How much energy exists within a specific space

 Weight: How much energy exists within a specific weight

Many times we confuse ourselves by speaking about one of them while forgetting about the other, and more often we forget about how one category may impact the other ie: large volume energies require large storage containers…which are often heavy. When we speak of energy density in maritime applications, both weight and volume can be challenges. At the end of the day, many types of shipping are measured on how many units of cargo they can carry and this can be impacted by the weight or volume of the energy system on board.

Why is this a challenge for the maritime industry?

As you can see in the figure above, the traditional fuels used by the maritime industry are very volume dense, meaning you can get a lot of energy into a small space. The fuels of the future; primarily Ammonia, Liquid Hydrogen (LH2) and Compressed Hydrogen (CH2 350/700 Bar) are quite the opposite, these are gravimetrically dense energies. Batteries are also a useful energy carrier – and often the cheapest overall solution when they are feasible. From the figure you can also see that batteries have low volumetrically & gravimetrically energy density, which means that you need large and heavy batteries to have sufficient energy. This limits the application of batteries to short sea applications (and of course as an energy buffer in all others). 

How does energy efficiency play a roll in this?

Energy efficiency is important because it is the multiplier different energies go through when they are actually used on board. What this means is energy densities are measured in theoretical energy contained per unit (volume or weight), however when the energy is consumed on board it is not the theoretical energy density that matters but the overall system efficiency. If energy has a high density but low efficiency it’s ‘Actual’ or ‘In Use’ energy density is much lower. Batteries shine strongly here because they have high efficiency and therefore are not penalized as severely as other energy carriers.

We’ve put together an interactive figure that displays the energy density for several conventional fuels such as MGO, and Diesel, and some of the new fuels proposed for use in maritime such as Liquid Hydrogen (LH2) or Ammonia. As a twist, we have added the option to see what these energy densities look like on board when the energy is actually utilized (in a combustion engine or fuel cell, etc). Just click the box under Energy Density: Theory or Reality and select «Reality».

Beyond the density of the energy itself, system (Balance of Plant) weights and volumes are important but require design and operational specifications to compare these appropriately. Beyond energy and system densities are a number of key issues to be considered such as safety, cost, and fuel availability.

If you have a maritime project you’d like to explore zero emissions on, we’re always looking to take on projects and offer advisory where we can add value

Do you want to learn more about electrolyser technologies? Check out our technology series: part 1, part 2 and part 3.

Week 42: Hydrogen projects

Hydrogen production project

It is finally Friday and we present the highlights from the past week. The EU Horizon 2020 project Haelous will demonstrate hydrogen production in Berlevåg, Norway, while Enapter plans to build a mass-production facility for its AEMs. You can also read about a solar and hydrogen energy solution for a preschool in Sweden and a Power-to-X project in the Netherlands. 

Future plans for hydrogen production in Berlevåg

Haelous, an EU Horizon 2020 project, will demonstrate hydrogen production form windpower in Berlevåg.  The wind park at Raggovidda has a concession for 200 MW, where only 45 MW have been built because of the export limitations. 2nd October Haelous partner Varanger Kraft informed that they plan to produce one ton hydrogen/day by electrolysis in the demonstration period. The wind park’s owner, Varanger Kraft, released on Wednesday their long-term plan for the exploitation of the hydrogen that will be produced in Berlevåg.

 The ammonia production plant will have a capacity of 110 000 tons a year, and could be ready by 2025. This would imply a hydrogen production capacity of about 50 tons a day, or 50 times the Haeolus project and about 125 MW of electrolysers. The main application is to supply ammonia to Svalbard as compensation for coal power. The demand at Svalbard alone is too low for cost-efficient ammonia production. ZEEDS is looking into the possibility of using the ammonia produced at Berlevåg as green fuel for ships.  


Mass-production facility for AEMs in Germany

Enapter, a company that designs and manufacture highly efficient hydrogen generators, has this week revealed plans to build its first mass-production facility for AEMs (Anion exchange membrane) in North Rhine-Westphalia, Germany. The «Enapter Campus» will include both production centre and research and development facilities. The new production site will be capable of production of more than 100 000 AEM electrolyser modules per year.

The construction is planned to begin in early 2021, and the Campus is expected to be operational in 2022. The Enapter Campus will be using renewable energy provided by Saebeck’s solar, wind and biomass plants, and from the Campus’ own solar arrays and hydrogen storage systems.

The AEM technology is patent-protected by Enapter. The AEM electrolyser use a semipermeable membrane to allow anions to pass, in contrary to a PEM electrolyser that let protons pass the membrane. This results flexbility, fast response time high current density and high purity hydrogen. This type of electrolyser does not require expensive noble metal catalysts materials or large amount if titanium. The electrolysers has a hydrogen production rate at 1,1 kg/hour, resulting in a capacity of about 26 kg/day.

Enapter electrolyser AEM hydrogen production

Enapter’s electrolyser has a capacity of 1kg per hour. Source: Enapter


Preschool with a solar and hydrogen energy solution

Construction company Serneke is, in collaboration with Mariestad municipality, building a preschool with a solar and hydrogen solution. The total costs of the project is SEK 65 million, and the preschool will be the first of its kind in Sweden. Construction will start this month in Mariestad, and the preschool will be built on the same property as the old Kronoparksskolan was located. The project is expected to be completed by January 2022.

Nilsson Energy is the supplier for the energy solution where solar cells will be installed at the roof. Hydrogen will be produced by surplus electricity, and the production and storage will take place outside the school building. Hydrogen gas will be converted to electrical and thermal energy during the dark periods of the year. 

preschool hydrogen energy solution

Illustration of the preschool with a solar and hydrogen energy solution . Source: Serneke


Power-to-X pilot project in the Netherlands

The Dutch energy company Alliander has contracted Green Hydrogen Systems (GHS) to supply electrolysers for for their large-scale Power-to-X pilot project in the Netherlands. The pilot is under construction at the Ecomunitypark in Oosterwolde. The contract covers the supply of three alkaline electrolysers with a combined capacity of 1,4 MW.

Solar-farm developer GroenLeven is also involved in this project. The electrolysers will be used to convert excess solar or wind energy into hydrogen, and the hydrogen will be stored and sold for use in transportation, industry, heating and other areas.


Hydrogen podcasts

Listening to podcasts is a good way to learn something new or to get an update on something you are interested in. We want to introduce you to three podcasts that has  energy and hydrogen on the agenda:

Greenpod (Norwegian)

Greenstats’s brand new Greenpod. New episodes are just around the corner. You can find the podcast here.

AksjeSladder (Norwegian)

The episode is about hydrogen and the development of hydrogen in the maritime sector, transport sector and the industry. Listen here

H2Podcast: Everything About Hydrogen (English)

Everything About Hydrogen is a podcast that converts the technical to the relatable and explores how hydrogen and its derivative technologies may change the energy world as we know it. Listen here.

Do you want to be updated on the development in the hydrogen market? Sign up for our news letter here. Contact us for an overview of existing and planned projects in Norway and the world: