Digital solutions are key to grid stability

Renewable Watch recently interacted with Pitamber Shivnani, President, Power Grids, ABB India, regarding the role of digitalisation in the renewable sector, on the sidelines of GRIDTECH 2019. Excerpts from the conversation.

What are the key transmission constraints in the renewable energy space in India?

Well, geography for one. The sheer size of the country means that, most often, utility-scale renewable energy sources are nowhere near the demand centres. To give an example of a recent project, we executed a substation for a key solar power player so far into the heartland of Rajasthan that it does not even show up on Google Maps. The nearest village from that substation is over 50 km away and Jodhpur, the nearest Indian city, is about 250 km away. Transmission through conventional means over such distances results in high transmission losses. The government’s Green Energy Corridors project aims to address a part of this problem through the deployment of high voltage direct current (HVDC) links that offer several advantages, above all, the following:

• HVDC transmission losses are less than half of AC transmission losses.
• With half the required right of way as AC transmission, the environmental impact and legal land issues are significantly reduced.

The recently commissioned multi-terminal ultra HVDC (UHVDC) link transfers 6 GW of clean energy from the hydropower-rich Northeast to demand centres around Agra. When completed, the bidirectional UHVDC link connecting Raigarh and Pugalur (in Tamil Nadu) will transfer conventional energy north to south, and when there is excess solar power in the south, it will carry clean energy from south to north. Then there is the issue of balancing the intermittent nature of renewables and its impact on such a dynamic grid.

How can digital technologies and solutions help address these issues?

Digital solutions are the key to real-time demand-supply monitoring and balancing, and maintaining grid stability. Applicable across the grid, digital technologies are transforming the entire grid from the field to the boardroom, also known as, “from operational technology to information technology”. Grid automation solutions allow utilities to harness the benefits of remote communications, cybersecurity care solutions, distribution automation systems and connected asset lifecycle management. Historically, network management systems like SCADA have provided greater control and monitoring over numerous processes. Digital technologies take this to the next level. Predictive and preventive care reduces downtime while increasing resource efficiency and enabling the integration of variable sources of energy like renewables.

What is the best way to manage distributed renewable energy generation along with the central grid?

Transmission and distribution of electricity through a power grid that combines power generated at all voltage levels from intermittent renewable sources along with traditional generation is very challenging. Power from traditional fuel sources can be scheduled while renewable generation is less predictable. High penetration of renewables requires an increased focus on managing/stabilising frequency and voltage. Renewable plant automation solutions help in simplifying plant operations, improving grid compliant renewable power production and maximising asset returns on investments. Such automation technology provides monitoring and control for individual plants, energy generation from a mix of renewable sources, through to the remote management of a fleet of plants, while ensuring grid compliance.

How can blockchain-based solutions be applied for optimising renewables?

Blockchain could be viewed as a transparent tool for keeping records – transactions are executed exactly once and an immutable record of all transactions is maintained in a fault-tolerant and tamper-proof manner. Moreover, if the ledger is publicly available, anybody can verify the correctness of its records. It shifts the trust we conventionally place in a third party to a distributed system and its embedded protocols. In broad terms, the application of blockchain can be classified in three categories:

• Registry service: Storing digital records in an immutable and auditable distributed ledger.
• Asset exchange: Asset creation and ownership transfer.
• Smart contract execution: Automate business processes through the execution of code.

The third point can play a large role in maximising the impact of renewable resources. Peer-to-peer transactions and grid transactions can easily be based on real-time pricing of renewable energy in the grid. Electricity is understandably a regulated area and prosumers will benefit from a well-designed policy that enables the use of this technology, which will require investment in understanding, setting up of technical standards and running pilots.

sources@renewable watch