Energy storage

CryoPower & renewable energy storage. What future options are there?

By October 8, 2018 No Comments

The UK horizon is changing. The sculpted green landscapes & glittering blue shores of Britain are becoming fractured by new manmade additions. Throughout the UK the sweeping arms of hundreds of wind turbines, majestically curve & coil through the landscapes.

Out at sea, the horizon has become a harvest ground & not always for fish! Farmers fields appear at first glance to shimmer like vast lakes in the sunlight. Only upon approach, do you realise that it is hundreds of thousands of solar panels glittering in the British sunlight.

The way we generate energy has changed exponentially in recent years, as the UK’s energy needs & usage has soared. The challenges we face are many & when it comes to renewable energy storage, we are constantly seeking cleaner & more sustainable ways of generating this beyond the traditional methods used in coal & gas production.

Solar & wind energy accounts for approximately half of the UK’s energy supplies. However, with ‘Zero emissions’ being at the forefront of the Government policies & the drive to achieve zero emissions by 2040; the race is on to ensure constant energy supply, while adhering to the global emissions standards.

The Independent reported in March of this year: “This meant that at the end of last year over half of our electricity came from low carbon sources, and most of that from wind and solar, overtaking nuclear power.

“These fast-moving trends will continue into the next decade as a new generation of offshore wind turbines come online and demonstrate the technology’s ability to provide the bulk of UK demand.”

Technological improvements in recent years have led to a dramatic fall in the cost of renewable energy.

Previous analysis by the International Renewable Energy Agency has demonstrated that onshore wind farms in particular already have the capacity to outcompete fossil fuels.

Critics of solar & wind farms have a very valid point when they query the stability & sustainability of this energy source; namely, what happens when the wind stops blowing & the sun goes in? In addition, the ability to store this energy poses its own dilemmas, as by its very nature, it can only be produced sporadically.

There have also recently been renewed calls to re-evaluate nuclear energy as a safe & sustainable renewable energy generator. However, incidents such as the Chernobyl disaster of 1986 and more recently Fukushima in 2015 reduce the public appetite for this technology.

‘The contribution of renewable energy sources to the grid plays a significant part to reduce the use of fossil fuels but it introduces further instability in the supply side of a system that already has a volatile demand profile (which is further exacerbated by domestic plug in EV). In Europe the 450GW of installed wind power only 22.5 GW (5%) is available as a pool resource that can be relied on. This problem is described as “wrong time” energy; the morning peak in demand is not necessarily met with sufficient wind or tidal power and conversely the energy potential of a late evening or night time breeze is of little use unless it can be stored.

Globally, electricity production is approximately 5000GW but the storage capacity accounts for only 2.2%. Pumped Hydro Storage is the most mature and accounts for 99% of the global energy storage. This involves pumping water to an elevated reservoir to increase its potential energy during “wrong time” energy periods and releasing the energy as electrical power with a hydro electric turbine during high demand periods.

Good examples of this in the UK are the pumped storage plants at Dinorwig and Ffestiniog in the Snowdonia region of Wales. The attractiveness of this technology is clear in environmental terms but also as a storage device as it has a huge storage capacity, Storage stability and long discharge time.

Unfortunately, the energy density and the environmental and economic impact of building a reservoir with a significant height above the generator precludes it from most applications. Compressed air and liquified are becoming more popular as energy storage systems (1) and the Dolphin Split cycle engine has a unique way to maximise the energy stored within the Liquid Nitrogen.


The supply/demand curve over one week highlights the need to import power at peak times and run systems at lower capacity other times.

Off-grid Isolated or islanded electricity systems which are not connected to main electricity systems generally reliant on diesel generators to supply.

Wholesale: The supply-side of the electricity industry, which encompasses the market where electricity is generated and sold. Storage offers intermittent balancing ,quality improvement and operating reserve

Transmission and distribution: The distribution of electricity is provided through regulated markets which obtain economic returns and incentives for the investment or deferral and management of the networks.

End users: Includes residential, commercial, industrial and electric vehicle electricity consumers or aggregators such as retailers that focus on back up ‘black start’

With this in mind, we can start to see that there are alternative energy generators & storage facilities. Many social media feeds are bombarded with the notions of how Government cut backs on wind & solar farms will be detrimental to the climate.

However, maybe it is time ‘green’ organisations started to consider using the social media highways to extol the virtues of or expand knowledge in relation to alternative energy source generators & storage opportunities. Dolphin N2 seeks to change this & help to educate & advise about the alternate storage solutions & open readers minds to innovative & alternative ideas.

Written by Katy-Jane Mason on behalf of Dolphin N2.