At the recently staged BSRIA event on ‘Energy Storage’ delegates felt that there is a lack of guidance in both Health & Safety and legislation surrounding such new technology. But 2016 could be the year that energy storage ‘takes off’ in the UK market. Battery manufacturers are poised to deliver economic storage systems which, when integrated with renewable energy sources, could breathe new life into the industry.
This seminar brought together experts in the various fields involved with the integration of battery storage into the distribution system. Speakers brought the audience a new perspective on the advantages, and potential problems, of this new industry.
Ant Wilson, AECOM, kicked off by saying how energy storage is changing. He amused the audience with images and explanations of slide rules, the Sinclair calculator, memory sticks and solar watches and lights. Ant said: “Things change rapidly”, adding: “We need to tap into the sun – it has so much potential. Regarding solar – it doesn’t need to be a sunny day!”
He went on to explain that a fuel is any material that can be made to react so that it releases chemical or nuclear energy as heat or to be used for work. And that we need to conserve fuel and power. There was good news: “Energy consumption is 20 per cent lower than in 2006. But we need to even out the demands by way of an ‘active passive system’.”
Jeremy Towler, Senior Manager, Energy and Smart Technologies, BSRIA:
Energy storage will be integral to smart grids, namely demand response: this will curtail or shift demand to remove peaks and troughs, flexible generation, storage and usage of energy. Jeremy said that “bulk energy trading was key. There is lots of ongoing research”.
Battery storage one of the most discussed technologies: especially commercialized batteries: lead-acid and sodium-sulphur. Many new technologies are under demonstration, prototype, laboratory and at concept stage. Jeremy said: “Cost is the main issue – the industry is working hard to drive it down.” There is development of new battery technologies in terms of ‘cyclability’, lifecycle cost, energy density (size), safety, operating temperature, degradation, etc.
Vehicle & building battery storage market about to take off: battery storage has been prohibitively expensive. Lead and lithium batteries are now commercially available for c. €1,000 ($1,200) per KwH. PV with battery storage which can have lower unit price than mains electricity. Many German manufacturers are now offering solutions. In April 2015, US Tesla launched Powerwall – battery storage aimed at the residential market. Further costs will be incurred for the battery management system and the installation itself. In June 2015, Mercedes launched 2.5KwH home battery – up to eight can be used in combination, providing 20KwH.
“The potential for significant cost reduction of some battery technologies provides real opportunity for significant deployment in multiple applications. In particular, Li-ion batteries prices are expected to reduce by over 60 per cent and flow battery prices by over 40 per cent by 2020.” (Study for the Australian Renewable Energy Agency, July 2015.)
Hydrogen fuel cells available for smart phones: in August 2015, Intelligent Energy announced a prototype hydrogen powered fuel cell which can power an iPhone for up to one week. Embedded within the phone, it emits small quantities of water vapour. The company already supplies fuel cells for a range of consumer electronics.
Tony Day, IERC, looked at the current issues surrounding energy storage, by explaining that technology needs to get out into the market place but it needs a revenue outlet which is certainly a business challenge. He said that energy storage benefits avoided costs and also provided some additional revenues and CO2 emissions reduction (with additional revenue potential). But some benefits may be difficult to quantify, to diffuse and, therefore, difficult to find investment.
Concentrated solar power with molten salt storage: CSP with molten salt storage is more economic than batteries and 24 hour operation has been achieved. There is scope for storage system cost reductions but these may be limited.
The business case: li-ion median price could fall by 47 per cent over five years (RMI 2016); stacked services offer greater potential for enhanced business cases (Lazard 2015); such ‘value stacking’ is difficult to quantify – see the Lazard Levelised Cost of Storage Analysis. Channels for various revenue streams need to be opened up.
GSHP as storage: deep piles will be thermally depleted without seasonal replenishment. Therefore, this is the best year-round heating and cooling solution. Shallow ground stores will be replenished by solar over the summer. However, this process is not suitable for grid services without additional short term storage on the load side.
CHP and thermal storage: CHP requires large thermal storage for efficient operation and load balancing. Adds to equipment and space costs but can require lengthy planning applications.
Deployment of storage: the issue is large scale versus distributed and energy storage versus short term grid services. Using heat storage for electricity smart grid applications and services is key as is hybrid solutions. We need to look to have improved total system efficiencies and optimisation of systems and the need for design tools and techno-economic models.
Tony finished off: “We need to optimise the technology.”
Bill Wright, ECA, considered the consequences, legal issues and health and safety issues.
Networks: The Electricity Distribution network is changing rapidly and we no longer have central power plants supplying out to hub. Local generation now feeds in to the network which is potentially unstable. Energy storage will become increasingly important and how do we manage this?
New standards: IEC 60364-8-2: Smart Low-Voltage Electrical Installations. This will ultimately form part of IET wiring regulations. It lays down basic requirements for connections of renewable energy systems, associated loads and electrical storage to existing grid and requires systems to be adequately protected. Further work on battery standards and descriptions is also underway.
Grid requirements: include stability; voltage control; active and reactive control; frequency control; load shedding capability; and coping with remote storage.
Energy storage – game changing: Tesla has announced 7KWH and 10KWH batteries for connection to PV systems and many others are entering the market. Payback is approximately 10 years depending on power cost and displacement but it will not provide standby power off grid. Larger systems being developed at cost down to $150/kwh. But beware of connections – fault levels could be high. Mass power storage equals “a real game changer”.
Smart grid: this balances needs between consumption and production of ‘Smart Electrical Installations’; manages data between consumers, prosumers and network operators; user should still be able to decide between local and / or grid supply.
How to protect the battery: battery storage brings electrical and safety hazards. Fault currents can be very high. We need to ask: Where is the battery mounted? What electrical and mechanical protection is required? Ventilation? Tesla incorporates short circuit protection but do other systems?
And: who will control the grid and production of electricity when there are many ‘prosumers’ and large amounts of storage? Grid control should be responsible for it – but how? We are just at the beginning of storage revolution!
Bill said: “Metering is essential – so you can get paid! But can I get off the grid? You should store electricity and energy when it’s cheap and put out when more expensive. Economics will drive the system – but it must be commercial. But how are you going to protect it and make profit from it?”
Dr Paul Westacott, Origami Energy – working with DECC – explained how he was improving the system value of renewables with storage and smart control: renewables output is variable and inflexible: they are often not well correlated to demand but they can present new challenges for electricity system operation. Storage is one way to help balance supply and demand.
Paul asked how does storage impact on the system value of solar PV? He had some “high level” conclusions: One of the first pieces of analysis to show PVS contribution to meeting winter peak. In summer – storage can reduce grid feed-in of solar PV by ~50 per cent. Interestingly, the value can be improved by: smart control and better forecasting; smoothing generation over larger areas equals more consistent output; utilising generation from different sources (e.g. wind and solar). He asked how does storage impact on the system value of solar PV and what are the broader context / next steps? He said: “DECC’s ambition is to make best use of all technologies together by knitting them together. But make sure everything stays in balance.
Timing of energy use is key, for example – demand is low on a summer Sunday. And Monday to Friday evenings in November to February would be the highest. These are the “pieces of the puzzle”. Our generation mix is going to be unpredictable. When there is not much sun and not much wind – this is worrying. We must consider the ‘next steps’.”
Hywel Davies, CIBSE, considered the need for guidance for the engineer and how this applies to a building level at the moment. He advised that the current status was “confusing” with “more questions than answers”. Indeed, Hywel said that he hasn’t got any of the answers! He said: “A robust, workable design to meet the client’s needs. Got to maintain and manage this. You’ve got a duty as a designer. I have never met a facilities manager who is a mind-reader! You’ve got to tell them what you want.”
He used this quote:
If energy storage is the answer – what are the questions?
“We are looking for the man that can find the right questions.” Sir Arnold Robinson.
Hywel’s final salvo was: “Who’s in control? And what is the strategy? How will it be commissioned?”
Myles Goddin, National Grid, began by quoting Thomas Edison: “My principal business consists of giving commercial value to the ideas of others. Accordingly, I never pick up an item without thinking of how I might improve it.”
The second energy transformation – another paradigm shift – creates challenges and opportunities: price volatility increases: renewables export at lower power prices; expensive peaking generation plugs the gap. Networks are congested during peak periods and asset utilisation is reduced and forecasting becomes increasingly challenging. Real time balancing and operations are difficult. There are opportunities to exploit reducing cost of technology and other flexibility tools.
Myles said: “Invention and innovation is not enough. Timing is key as is the right time and place and timing. As is the future of the electronic age – but we need a price arbitrage. Edison is more relevant today then he was back then. How much storage do we need globally? Which model would we look at? I haven’t got the answers! But combinations are key and technology is the enabler.”
Value proposition – can future energy storage facilitate matching of energy supply and demand in a growing area of intermittency and inflexibility?
Challenges: Monetise – will these investments be able to produce a big enough return? There are a few projects in development – is finance an issue? A vibrant and competitive market will stimulate innovation.
Energy and sustainability has been at the forefront of discussion in recent years and this innovative network aims to establish communication amongst peers; drawing on the expertise of various representatives in the industry. The group meets three to four times a year to discuss challenges and case studies on energy and sustainability issues.