Hydrogen on the Rise: A renewable energy based storage solution

A new application of hydrogen is being deployed that’s helping solve humanity’s ever-evolving energy woes. Traditionally, hydrogen has a large number of applications, used in everything from industrial products to food packaging. It’s also a primary component in ammonia. Ammonia used in fertilizer and industrial processes amounted to 160 million-tons worldwide in 2011 alone.

Not surprisingly, the market demand for new, less expensive sources of hydrogen is driven heavily by fertilizer and manufacturing processes. However, a new market demand is emerging for hydrogen in another sector: energy. Power plants in Germany and in Canada (using wind and natural gas, respectively) are today supplementing their primary electrical generators with advanced configurations of hydrogen technologies. These retrofits help plants save money by smoothing supply, and converting excess electricity generated into storable hydrogen gas, which can be returned to electricity using a turbine generator or a fuel cell.

For natural gas-fired plants, there are enormous expenses associated with starting the generators from scratch—from the amount of fuel it takes to the time it takes to gain momentum. To mitigate this concern, operators often continuously run their turbines, regardless of electricity demands. Fuel and energy are, therefore, wasted, as the additional electricity generated is more than the plant will be paid for or is expected to supply.

Wind farms face a similar supply-demand problem. Although wind is free (unlike natural gas), it’s often generated at times when there isn’t a demand for the electricity (off-peak hours). As a result, there tends to be an abundant supply of low-cost, renewable energy that goes unused, and never paid for.

The hydrogen solution
To cut costs and expand margins, the hydrogen power plant strategy is simple: store extra electricity supply as high-energy hydrogen gas, and deliver it later as electricity, when it’s not only in demand but also revenue-generating.

In the last two years, there’s been a lot of public and private attention directed at hydrogen technologies, especially in distributed generation and renewable hydrogen energy. To be clear, hydrogen is an energy carrier, not a source, as it doesn’t actually make energy. It needs the reaction with a catalyst and oxygen to release its contained energy, which often occurs in a fuel cell. Hydrogen is not naturally occurring anywhere on earth, such as oil or coal or even sunlight. Rather, hydrogen must be obtained from processes like electrolysis (running direct current through water to make H2), or reforming natural gas (which contains hydrogen). As this first method demands energy usually derived from fossil fuel, and the latter is derived directly from a fossil fuel, it’s seems reasonable to question hydrogen as a clean energy solution.

Hydrogen produces only pure water when used for energy, so if it takes carbon-intensive fuels to make the hydrogen, then why explore it as a source of clean energy? Fortunately, there are many sources of energy in the world that don’t contain fossil fuels. Indeed, hydrogen can—and has been—created through electrolysis powered by clean energy, and more projects combining renewable energy and hydrogen are being developed right now.

Hydrogen & wind
In no industry are the benefits of supplemental hydrogen systems more apparent than for wind energy. Diminishing tax credits and subsidies have encouraged developers, operators, and owners to explore new ways to increase margins on current and developing wind projects. Additionally, in the wind industry, everyone knows and fears the concept of “curtailment”—the forced shutdown of renewable energy infrastructure by utilities or other PPA recipients. Curtailment occurs when the grid is overloaded by electrical supply, and utilities have contracts with suppliers other than renewable wind and solar. When curtailment occurs, wind turbines and solar panels lay idle. During curtailment, renewable energy operators’ assets sit and depreciate, generating little or no revenue. In certain regions, like Texas and Oklahoma, curtailment occurs as often as 50% of generating time.

A hydrogen-based energy storage system provides operators of wind-generation assets a solution to the issues of curtailment and diminished returns from generating during off-peak hours. Storing less valuable energy generated in curtailment or off-peak periods, wind farm operators can return the energy to the grid in higher value, on-peak times, using a hydrogen fuel cell. The differences in tariff prices written into wind farm PPAs is often considerable enough to consider storage, and many inherent characteristics of fuel cell technology make it a front-runner for future energy storage projects.

Hydrogen & energy storage
In a commercial sense, the hydrogen debate has been gridlocked for years, without much attention in political and business agendas because of the perceived high costs of the technology. Today, new technologies and unique business models present a strong case for implementing hydrogen-based energy storage—especially when paired with intermittent renewable energy sources. Compared to alternate energy storage methods, hydrogen has real advantages that all consummate cost reduction and margin expansion.

For one, the cost of electrolyzers (what makes hydrogen from electricity) has decreased 25% in the last 10 years, and new innovations in fuel cell technology have made the systems more efficient. Consider that the average US coal-fired power plants are 40% efficient. And, the round-trip efficiency of hydrogen storage systems (“round-trip” referring to the energy loop of electricity-to-hydrogen-to-electricity again) has now reached 45% efficiency. Electrolysis techniques have reduced the need for additional transformers, so systems can adapt to the current and voltage of wind turbines and transmission facilities. This reduces capital cost for additional transformers and increases system efficiency due to the system losses associated with transformer technology.

Secondly, fuel cells are a much more suitable storage technology for grid applications because they provide a constant level of energy, as opposed to alternative methods such as batteries or compressed air, which decrease in output over time.  

Niche markets appear to be fully embracing the potential of hydrogen. Germany already has hydrogen-power plants, and a new transportation project that’s building 50 new refueling stations to supply hydrogen-powered vehicles. In the US, hydrogen buses are in operation in Austin, Birmingham, Cleveland, and several other cities. There’s also a large bus fleet in Reykjavik, Iceland where there’s a vast supply of renewable energy to cheaply create hydrogen fuel. OEM are already predicting an energy market transformation with a planned rollout of hydrogen, fuel cell vehicles starting in 2014 from Mercedes Benz, BMW, Toyota, General Motors, Nissan, Honda, and Ford. Hydrogen energy, it seems, is no longer an idyllic power solution but, rather, a market-based clean energy solution.

 
Samuel Sterling is a marketing and business development consultant for Angstrom Advanced Inc.

Angstrom Advanced Inc. is a technology manufacturer that specializes in designing and deploying residential, commercial, and industrial-scale electrolyzers used for renewable energy storage, transportation fuel, natural gas plant peaking, distributed generation, and more.

Angstrom Advanced Inc.
www.angstromadvancedinc.com