Setting up rooftop solar for residential and commercial consumers has been a challenge worldwide due to its high cost and the intermittency of the energy source in itself. While the costs have come down and net metering options enable faster returns on investments, incorporating energy storage to ensure power reliability is still quite expensive. As the industry is looking at technology innovation to cut down costs further, new business models are coming up that combine energy generation and consumption with artificial intelligence (AI) and internet of things (IoT) to optimise the value chain and increase revenues. QBots is one such company that deploys AI to build and operate a virtual or federated power plant (FPP). An FPP aggregates prosumers (or distributed energy generators and consumers) and uses the flexibility in their energy demand to deploy renewables and battery energy storage systems, enabling localised trading and balancing of power.
Federated power plants
QBots’ AI system has two levels of prediction and control: one at the site-level and the other at the network-level. At the site-level, AI technology allows consumers to respond to notifications from the electricity grid to shift their electricity demand and use battery energy storage systems, while fulfilling their normal energy requirements. On the other hand, at the network-level, QBots’ algorithms locally aggregate a large number of prosumers to create virtual power plants or FPPs to actively manage the distributed generation unit. Such a system is then used to trade energy between the virtual power plant network users through a peer-to-peer (P2P) energy trading platform. This P2P platform allows consumers and generators to carry out transactions amongst themselves, without the interference of regulatory authorities. Thus, the prosumers can participate in the wholesale electricity markets in a simplified manner and provide ancillary services through the excess energy stored in their battery energy storage systems. Through effectively managing energy generation, energy exchange and consumption within small networks, the QBots system provides effective balancing services to the local distribution and transmission utilities. Thus, consumers benefit not only by reducing their bills, but also by earning revenues by selling power, flexibilising their energy consumption and using battery storage technologies as well as electric vehicles (EVs) to participate in the wholesale energy trading.
Incorporated in 2017 by Dr Li Yao (founder), along with Vijay Natarajan (co-founder), QBots aims to bring IoT, data analytics, machine learning and automation capabilities to energy management and storage. The organisation has been working on several projects in the UK over the past year, which are briefly discussed below:
- HoneyComb V2G: This is a vehicle-to-grid (V2G) project, which was carried out alongside the Manchester City Council and various other stakeholders to enable large-scale deployment of bidirectional EV charging points for charging EVs as well as using their stored energy to feed into the grid during high energy demand time periods. By sharing the energy storage capacity of EVs with smart buildings and renewables, QBots has built a virtual power plant of about 50 MW capacity in Manchester.
- CityVerve: QBots has worked with Bruntwood and the University of Manchester, through the smart city programme and identified three buildings in the region – Citylabs 1.0, Bright building and James Chadwick Building. The company is carrying out flexibility modelling and analysis by using energy and building management system data to deliver demand side response, facilitate energy savings and reduce carbon emissions.
- Exeter city futures: QBots has also executed a project with Exeter City Council estates over a period of four months to carry out a detailed analysis of the energy data from five sites in Exeter. QBots designed a smart system with battery storage rated at 500 kW/500 kWh for one of the sites, which had an existing 1.5 MW solar installation. Using the AI technology, the company has improved the utilisation of on-site generation, reduced electricity bills and provided additional income through ancillary services and energy trading.
In future, the company plans to continue providing smart energy management solutions through solar power generation and energy storage systems using AI techniques integrated into the QBots platform. Such new ideas can also fit into the Indian solar space, especially in the rooftop segment. Many states are implementing the Smart City programmes, under which commercial and residential rooftop systems are being promoted. In addition, states like Delhi have rolled out virtual net-metering provisions to allow communities and large residential complexes to integrate their solar generation. Thus, a platform like QBots, which allows energy trading among different users, can reduce the stress on discoms to manage the intermittent deviations and aid the efforts to achieve the 40 GW target.
New developments in the energy storage technology space have changed the way the conventional grid functions to enable greater renewable energy adoption. Amongst the available technologies, flow batteries have the advantage of providing large-scale energy storage. However, a wider adoption of these batteries has been limited due to the use of expensive and toxic fluids that require high operating temperatures. Researchers at Stanford University have developed a new type of flow battery using sodium and potassium, which can be mixed to form a liquid metal at room temperature. This fluid can then be used on the negative terminal of the battery as the electron donor. Theoretically, this liquid metal has at least ten times the available energy per gram as other available fluids for the negative-side of a flow battery.
In order to keep the negative and positive materials separate, while allowing current flow, the scientists have developed a suitable ceramic membrane made of potassium and aluminium. The new fluid along with the ceramic membrane can more than double the maximum voltage of conventional flow batteries. The higher voltage of the battery directly translates into an increase in the amount of energy stored by a battery of the same size, which further brings down the cost of production. The experiments conducted at Stanford have revealed that the ceramic membrane very selectively prevents sodium from migrating to the positive side of the cell, which is critical to the success of the membrane. The group has also experimented with a thinner membrane, which boosted the device’s power output at room temperature. The researchers have also experimented with four different liquids that are non-water-based for the positive side of the battery to further improve its performance. The team has developed a prototype, which has demonstrated promising results by remaining stable for many hours of operation. According to the researchers, while a lot of work still needs to be done to scale up the technology for commercial operations, this new battery could certainly enable much higher use of solar and wind power using earth-abundant materials in an affordable manner.
Source: Department of Materials Science and Engineering, Stanford University, USA
Photosynthesis is the process by which plants convert sunlight into energy by splitting the water molecules into oxygen and hydrogen. This can essentially be considered as a form of solar-to-energy conversion process. Through replicating the photosynthesis process artificially, the hydrogen generated as a byproduct can be stored easily and used as a green source of energy. In a study carried out by researchers from the Reisner Laboratory, St John’s College, University of Cambridge, semi-artificial photosynthesis has been used to explore a new method for producing and storing power generated from solar energy. The researchers used natural sunlight for unassisted water-splitting into hydrogen and oxygen by means of a mixture of biological components and manmade technologies. Natural photosynthesis is relatively inefficient as it only produces the bare minimum amount of energy needed by the plant for survival (around 1-2 per cent of what it could potentially convert and store). However, by using artificial or semi-artificial photosynthesis methods, a greater amount of solar energy can be absorbed and converted into useful byproducts. Artificial photosynthesis has not yet been used on a large scale for clean energy generation as it requires catalysts that are expensive and toxic in nature. But an emerging field of semi-artificial photosynthesis is focused on overcoming these limitations of fully artificial photosynthesis by using enzymes to create the desired reactions.
To carry out semi-artificial photosynthesis, researchers at Cambridge have reactivated a process in algae that had been dormant for millennia. Over a long period of time, an enzyme present in algae, known as hydrogenase, had become deactivated as it was not necessary for its survival. This enzyme is capable of reducing protons into hydrogen, a property that is desirable for splitting water into hydrogen and oxygen. It is now being used to significantly improve the amount of energy that can be produced and stored through artificial and completely solar-driven photosynthesis. These findings can contribute towards developing new and innovative methods for solar energy conversion and energy storage in the form of hydrogen as well as reducing carbon emissions to lower greenhouse gas emissions and prevent climate change.
Source: Department of Chemistry, University of Cambridge, Cambridge, UK