Something rather important happened in Galle last week with remarkably little fanfare. Sri Lanka’s first commercial-scale Battery Energy Storage System was connected to the national grid. It can store electricity when we have too much and give it back when we need it and that could remove one of the biggest obstacles standing between Sri Lanka and substantially cheaper renewable electricity.
Sri Lanka has spent years talking about solar panels, wind farms, renewable-energy targets and reducing the country’s dependence on imported fuel. On September 10, something rather less glamorous but potentially just as important happened at Bataduwa near Galle.
Sri Lanka’s first commercial-scale Battery Energy Storage System, or BESS, began operating on the national electricity grid.
Submit Your Press Release
Get your company news, announcements, launches, appointments and events in front of a wider audience.
The installation has a capacity of 10 megawatts and can store 40 megawatt-hours of electricity. Put simply, it is an enormous rechargeable battery connected not to somebody’s house but to the electricity system itself.
That matters because renewable electricity has always had an inconvenient problem. The sun does not necessarily shine when Sri Lanka most needs electricity and the wind does not wait for the evening peak before deciding to blow.
Solar power can produce large amounts of electricity during daylight hours, precisely when household demand may not be at its highest. Then evening arrives, people return home, lights and air-conditioners are switched on and demand rises just as solar generation disappears.
Traditionally the electricity system has had to replace that disappearing solar energy with another source capable of producing power when required. In Sri Lanka that has frequently meant hydro where water is available, coal or considerably more expensive oil-fired generation.
A battery changes the equation.
Instead of wasting or restricting renewable electricity when supply exceeds what the grid can immediately absorb, some of that energy can be stored. When demand rises later, the battery discharges it back into the system.
The Bataduwa installation can provide its rated 10 MW output for approximately four hours. One battery will not transform Sri Lanka’s electricity system, but Bataduwa is not intended to remain alone.
The original procurement called for 160 MW and 640 MWh of standalone battery storage divided among 16 grid substations around the country, with individual 10 MW/40 MWh projects planned for Kilinochchi, Vavuniya, Polonnaruwa, Valachchenai, Ampara, Vavunathivu, Monaragala, Mahiyanganaya, Chunnakam, Beliatta, Galle, Matara, Hambantota, Old Anuradhapura, Maho and Panadura.
That means what has just happened in Galle should be regarded as the first piece of a much larger electricity-storage network.
And Government ambitions have already become considerably bigger.
The National System Operator is now pursuing another 250 MW/1,000 MWh of standalone battery storage and has also invited proposals for 150 MW/600 MWh of battery systems integrated with existing ground-mounted solar plants.
If those projects materialise, Sri Lanka could move relatively quickly from virtually no commercial grid battery storage to hundreds of megawatts of it.
That is not simply an environmental story.
It is an economic one.
Sri Lanka spends valuable foreign exchange importing fuel. Every additional unit of electricity that can economically be generated from indigenous renewable resources rather than imported fossil fuel potentially reduces that exposure.
But simply installing ever more solar panels does not solve the problem. An electricity system must remain balanced every second of every day. Generation and demand have to match, voltage and frequency must remain stable and somebody must be able to respond rapidly when supply suddenly changes.
Batteries are unusually good at doing that.
They can respond almost instantaneously, absorb surplus electricity, release it when required and assist with frequency and voltage control. That makes them useful not merely as enormous rechargeable batteries but as tools for keeping an increasingly renewable electricity system stable.
Sri Lanka’s own electricity planners have recognised the problem. The Public Utilities Commission approved bringing forward battery storage originally envisaged for later years because renewable generation was growing faster than expected and battery prices had declined.
Cabinet subsequently approved accelerated procurement. The Government has said the country’s increasing night-time peak demand is appearing roughly two years earlier than anticipated in the Long-Term Generation Expansion Plan, strengthening the case for storage.
There is therefore an intriguing possibility.
For decades Sri Lanka’s electricity debate has repeatedly returned to the same argument: what power station should we build next?
Coal, LNG, hydro, solar, wind or something else.
Storage introduces a different question.
How much more electricity could we obtain from generating capacity we already have if we became better at deciding when that electricity is used?
A megawatt-hour of solar electricity produced at noon and unwanted at noon is not particularly useful if the country desperately needs it at seven in the evening. Store it for seven o’clock and its value changes.
There are, however, questions NEWSLINE believes should accompany the enthusiasm.
Battery storage is not free electricity. Somebody pays to build the facility and the operator must recover the investment and earn a return. The relevant comparison therefore is between the cost of storing and later supplying that electricity and the cost of generating an alternative unit when it is required.
Those numbers should be transparent.
The Bataduwa project has reportedly been developed by Galilee BESS Limited, a subsidiary of WKV Hydro Technics, ultimately owned by Singapore-based Khen Energy Limited. The broader programme
is structured on a Build, Own and Operate basis, with private developers responsible for financing, constructing, operating and maintaining the batteries over a 15-year operating period.
That means taxpayers do not simply purchase hundreds of millions of dollars of batteries upfront. But electricity consumers ultimately pay for the storage service through the power system.
The tariff therefore matters enormously.
How much will the National System Operator pay for electricity stored and returned from these facilities? What was the winning price at Bataduwa? How does that compare with the cost of oil-fired generation displaced during peak periods? What return is being guaranteed to the developer and who carries the risk if battery performance deteriorates faster than expected?
There are technical questions too.
Large lithium-based battery installations require rigorous fire protection, thermal management, monitoring and emergency procedures. Sri Lanka’s regulators and standards authorities have already been working on safety and technical standards for BESS installations as the technology begins spreading across the country.
Those safeguards will become increasingly important as dozens of installations appear.
But none of those questions diminishes the significance of what has happened at Galle.
Sri Lanka has a target of obtaining 70 percent of electricity generation from renewable sources by 2030. Achieving anything approaching that level requires more than simply constructing solar and wind capacity. The grid itself has to become capable of accepting and managing large quantities of variable electricity.
Storage is one of the missing pieces.
It could also become increasingly relevant to the hundreds of thousands of rooftop solar installations appearing across the country. The electricity system of the future may look very different from the old arrangement in which several enormous power stations generated electricity and everybody else merely consumed it.
Homes and businesses are increasingly becoming generators. Large solar and wind farms will feed variable electricity into the grid. Batteries will store some of it. Eventually an electricity interconnection with India could provide another mechanism for importing or exporting power depending upon availability and price.
The National System Operator rather than the old vertically integrated CEB structure will increasingly have to orchestrate that complicated market while ensuring somebody’s light still comes on when the switch is pressed.
That makes the modest-looking battery installation at Bataduwa considerably more important than its 10 MW rating suggests.
Sri Lanka has just demonstrated that commercial grid-scale electricity storage can actually be connected and operated here.
Now comes the real test: whether the remaining projects arrive on schedule, whether the tariffs represent value for consumers and whether storage actually allows the country to replace expensive fossil-fuel generation rather than merely becoming another cost added to the electricity bill.
Be that as it may, for more than a century electricity had one particularly inconvenient characteristic: once generated, enormous quantities of it were difficult and expensive to keep until later.
Sri Lanka has just started changing that.
The sun may still go down at six. Our solar electricity no longer necessarily has to go down with it.
