Table of Contents
1 BLOCKCHAIN AND ENERGY
1.1 The Challenges
With most of the greenhouse gas emissions tied to the energy sector and centralised utilities worldwide relying on selling more power to stay profitable, the energy industry requires a major shift from its current form of generation, distribution, and management to truly contribute to environmental sustainability. A fundamental challenge coming from this shift is the increasing complexity of physical and information exchanges in the distribution network.
Renewable sources’ distributed and intermittent nature makes new and adaptive energy systems fundamental. Renewable energy resources installation is growing at a quick and steady pace. As a result, energy networks undergo rapid transformations to accommodate the increasing load these decentralised technologies produce.
A scenario with net-zero anthropogenic carbon emissions by 2050 would require 70 to 85% of renewables providing electricity around the globe. Political awareness has led to significant digitalisation measures such as the smart meter rollout in some countries . The future of the energy sector depicts an inefficient centralised approach. Instead, it will be well known for configuring a complex harmonisation of prosumers and intelligent devices communicating in real-time by leveraging information and communication technologies (ICT).
New business models emerge from this leverage, particularly those using blockchain coupled to the internet of things (IoT) . Although the conventional electricity grid was not designed to handle increasing dynamic loads because of rapidly growing electric vehicle utilisation, these machines have gained popularity due to their potential ability to provide ancillary services.
1.2 The Promises
In their extensive review, Andoni et al. identify the following areas as likely candidates for practical near-term applications in the energy sector:
- Sales and marketing
- Trading and markets
- Smart grid applications and data transfer
- Grid management
- Security and identity management
- Sharing resources
These are general categories, with multiple applications in each area, many of which are described in the accompanying sections in this article, including aggregation and optimisation of behind-the-meter assets, P2P power trading, virtual power plants, management of EV charging networks, energy communities, and so on.
While use cases indicate early development stage applications, only the future will tell which categories will be successfully implemented and eventually grow to become dominant in the years ahead. Renewable energy certification (REC) applications were the first to reach the market. The commercialisation of these first market applications has been catalysed by creating a shared blockchain technology platform with enhanced functionality for energy industry applications provided by the EWF. And while the REC applications were the first to reach the market, the most transformative applications are likely to be in the area of P2P trading .
2 ASSET TOKENISATION
2.1 How Does It Work?
Asset tokenisation is an expansion of blockchain technology that allows digital resources to be bought, sold, and traded on blockchains. Tokens represent assets on the blockchain in order to facilitate transactions. Blockchain technology, which is in the spotlight through the launch of cryptocurrency, is being expanded to many other business practices. One such expansion of blockchain use is about converting rights to an asset into digital values that can be exchanged on blockchains. Tokenisation on blockchains has been a definite trend since early 2018; diamonds, paintings, company stocks and real estate, it seems that everything is a potential token. Even projects aim to tokenise forests, oceans, species, and other “exotic assets.”
In this context, asset digitalisation means that physical assets are turned into digital assets. Then, the latter can be partitioned, and a digital token can represent the subunits. Figure 2 illustrates this process. All tokenisation is digitisation but not vice versa, and that is because tokenisation is a unique process that supports fractional investment and ownership. Representing real assets as digital tokens allow its issuers and holders to achieve the benefits of cryptocurrency, that is, security, liquidity, and immutability, to real-world assets. An example of the benefits of tokenisation can be seen in the faculty of “fractionating ownership” of real assets.
The electric power system currently faces the challenge of integrating an increasing share of variable renewable energy sources, such as rooftop photovoltaic panels on housing. This means transforming the consumers into producers of electricity, so-called prosumers, and dramatically increasing the power systems control complexity.
In order to increase the consumption of electricity, mainly from renewables, within local communities, thus reducing losses and stress of both transmission and distribution networks, the proposed idea is to enhance peer-to-peer energy exchanges leveraging upon an increasing penetration of internet of things systems, which brings a continuously increasing level intelligence at appliances, combined with the deployment of energy storage and the electrification of heat uses.
2.2 Benefits of Asset Tokens
In addition to facilitating segmented ownership, asset tokenisation offers the following benefits.
- Global access to investments: Currently, only people in top economies have easy access to vast investment opportunities. Energy Future and Option contracts are traded in bulk volumes, making it burdensome for individuals. Asset tokenisation would make investments universally accessible thanks to fractional ownership and access to the markets without intermediaries.
- Greater liquidity: Subdivided ownership and universal access to investment opportunities support better liquidity for the underlying assets. In addition to allowing smaller investment amounts and having access to more markets, digital assets are just easier to trade. Trading digital tokens on a blockchain is far easier than selling physical real estate, ships, or diamonds.
- Reduced need for intermediaries: There is less need for middlemen with blockchain technology. Tokens can be traded straight between buyers and sellers without banks, lawyers, or other intermediaries. However, periodically, intermediaries may be required to verify the existence and condition of the underlying asset.
- Faster transactions: On blockchains, assets can change hands at the speed of thought. There are no forms to complete, papers to sign, waiting periods, and so forth. Most blockchain platforms can be accessed from a web browser or a mobile device, and transactions can be executed in real-time.
- Transparency: Blockchains, via the anonymous cryptocurrencies they support, have been associated with criminals, terrorists, and con men. In reality, blockchain is one of the most transparent financial systems ever invented. In fact, every single transaction can be publicly traded on digital ledgers, making them much more transparent than a traditional banking system.
- Immutability: Immutability refers to the fact that once a block of transactions is validated and added to a blockchain, the information is almost impossible to alter or delete. This is because the chain of blocks and the transactions they contain are replicated on computers located throughout the world. If a bad actor tries to alter a transaction, all the other computer operators (called miners) would know and would not allow the alteration. This feature makes transaction history not only transparent but secure.
2.3 Fungible and Non-Fungible Tokens
Tokens are broadly regarded as two categories, fungible tokens (FT) and non-fungible tokens (NFT), based on whether they are identical and interchangeable or not. FT are interchangeable, indistinguishable, and divisible. On the other hand, NFT cannot be switched for other assets of the same type and are an indivisible entity. In an energy transaction system, assets with a bound Guarantee of Origin have a unique identifier and are not interchangeable; hence they can be implemented as NFT. Conversely, if energy assets are considered swappable, then tokens representing them can be broken up, traded in parts, and carried out as FT. Both implementations are relevant in energy transaction systems .
Energy system managers and researchers are designing, implementing and performing tests for unified transaction systems and energy assets characterised as Fungible and Non Fungible Tokens. The main idea behind this is to incorporate all the stakeholders and business relationships into a transparent and decentralised solution to address the identified gap in both energy marketplaces and literature. A system like this would allow energy assets to be traded across a decentralised peer-to-peer network. A transparent system with inherent immutability, authentication, access control, provenance tracking, and the ability to encode business logic into smart contracts would allow for transaction automation. It may be repurposed for future microgrid transaction systems. Finally, transaction throughput and latency metrics can assess a transaction system’s performance.
Based on the aspects discussed above, the main contributions of these types of developments include the following:
- Transaction platforms include prosumers (electricity consumers that produce part of their electricity needs from their own power generation facilities) and EV owners, utilities and energy storage providers. This system’s trading relationships and energy assets are encapsulated in a blockchain structure with token-level consensus policies reflecting the identified stakeholders.
- The main stages in the lifecycle of all tokens were defined as Create, Bid, Transfer and Redeem. The methods and algorithms to take the token through the lifecycle were separately developed for NFT and FT due to the different characteristics of these token implementations.
- A proof of concept was implemented on the Hyperledger Fabric blockchain platform, and the developed algorithms were encoded as smart contracts. Experiments were designed and executed to test the implementation based on transaction throughput and latency metrics.
But that is not all. Besides utilities, non-fungible tokens are also proof of ownership of a piece of digital art. They were conceived as a way to allow digital artists to assert the originality of their work. An entry into a digital ledger is created when an artist mints an NFT of their work. So, What is the environmental footprint of NFTs? It is difficult to estimate the metrics therein because many steps in the minting process do not have a known carbon footprint. Some https://digiconomist.net/ethereum-energy-consumption forecast a single Ethereum transaction’s carbon footprint at 33.4kg CO2, while others estimate that an average transaction specifically for NFTs has a carbon footprint of about 48kg CO2. These estimates tell us that one NFT transaction is likely to have a carbon footprint more than 14 times that of mailing an art print . We must remember that each time an NFT is minted or sold, that is another transaction.
Bitcoin and Ethereum run using Proof-of-Work (PoW), which is the main reason behind its high energy intensity. One alternative is to use a blockchain running with a different system, such as Proof-of-Stake (PoS). PoS blockchains like Tezos or Polygon (all three support NFTs) do not rely on massive computing power and thus consume much less electricity. Ethereum itself says it is transitioning to a PoS system, and its website is calling for new “stakers,” who will be responsible for securing the network and processing its transactions. Some claim that PoW blockchains will also be acceptable if they run on renewable energy.
2.4 Examples of Tokenised Energy Assets
We are now aware that PoW-based blockchain ecosystems consume vast amounts of energy that could have been used for other purposes, and energy-inefficient ecosystems now take over the cryptocurrency and DeFi markets. Most often, a lot of gas is being misspent. Tokenising energy assets is the next big step in Decentralised finance (DeFi) — not only because it’s profitable but also has the potential to employ blockchain technology to promote green, clean and eco-friendly energy sources.
Energy tokens let anyone, anywhere in the world, gain effortless exposure to the power market. Investing in the clean energy transition through tokenised assets can be very profitable since these have the same functionalities as other DeFi assets — for example, they can be staked to generate a source of blockchain-based passive income. Assets such as ENEDEX tokens  enable individuals to invest in various green energy sectors indexes, such as solar energy and photovoltaic technologies, biomass energy made from plants, low carbon energy produced with wind turbines, and technologies using hydrogen as fuel.
Sun Exchange  is a South African blockchain-based solar micro-leasing marketplace that has introduced a digital network and its own token. Members can buy solar photovoltaic (PV) cells for around $10.00 per cell and lease them to be deployed in solar projects for businesses, hospitals, schools, and other organisations through its online platform. Solar equipment owners receive lease rental payments, paid by preference in fiat currency or cryptocurrency, while consumers enjoy the benefits of affordable clean energy.
In order to facilitate P2P exchanges of clean energy, local low-voltage two-step electric markets have been designed . After the day-ahead market clearing, a quasi-real-time second step is proposed to sell the unexpected excess or shortages of electric energy among peers and balance demand and consumption locally. This kind of quasi-real-time solution, namely within 15 minutes and without any intermediary, can be successfully and safely implemented only thanks to the blockchain technology and energy tokens like the one introduced by Energy Web.
The Energy Web Foundation is a non-profit institution established in 2017 by the Rocky Mountain Institute and GridSingularity. The objectives of the EWF are basically two: i) to work with energy sector stakeholders to identify, assess, and help bring to market blockchain application; ii) to build an open-source, Ethereum-based, consortium blockchain infrastructure upon which implementing application in the energy sector.
The Energy Web Chain’s core value proposition, i.e. an Ethereum-based, consortium blockchain, looks like a good basis on which a slightly different modified platform may be built. This is called Proof of Authority (PoA). Because of such PoA consensus, the cost of creating blocks is much lower with respect to those in PoW. Therefore, transaction costs are much lower in EWC with reference to Ethereum (main net). In addition, a platform that inherently provides a greater level of data privacy would also be a desirable feature to have. The Energy Web Token (EWT) is the Energy Web Chain’s own cryptocurrency.
More and more, the entire markets are now conceived considering any kind of consumer/prosumer expectation (economic, reliability and privacy points of view), together with the needs of the other actors involved. In this way, the information technology and the electric infrastructures can work effectively, besides relying on smart metering and modern billing systems. Network aspects have been correctly taken into consideration, e.g. assuming load flow checks to be performed by the distribution system operator, as well as security issues, mitigating any cheating, both from single users and group attacks.
3 SMART ENERGY CONTRACTS
3.1 Smart Contracts Fundamentals
In this section, it is well explained what constitutes a blockchain infrastructure, referring to its vital ingredients, such as distributed data storage, a peer-to-peer connection, a consensus mechanism, encryption algorithms, and finally, the core of what makes a blockchain automated and executable: smart contracts.
Blockchain facilitates security services such as authentication, authorisation, integrity, non-repudiation and anonymity for all real-time applications. In most blockchain applications, network nodes are referred through their public key, ensuring anonymity. Plus, the use of a “Merkle tree” that creates chained hashing maintains well-formed blocks, making the blockchain virtually unhackable. Blockchain enables transactions between consenting individuals who otherwise would not be able to trust each other.
Ethereum’s aim is to enable developers to create autocratic consensus-based applications that possess scalability, standardisation, feature completeness, ease of development, and interoperability. Ethereum attains this by constructing fundamentally an abstract foundation layer, a blockchain with built-in Turing-complete programming language, which can be employed by everyone to deploy smart contracts and decentralised applications. Developers can thus create proprietary ownership rules, transaction formats, and state transition functions.
The Ethereum Virtual Machine (EVM) is a huge decentralised computer enclosing millions of objects called “accounts”; accounts can hold internal databases, execute code, and communicate with each other, a smart contract being one of them . The EVM compiles instructions from a programming language into low-level code for the computer it runs.
Blockchain’s core disruptive element is the possibility of agreeing on the content of a database that is shared among equally powerful nodes which are foreign to each other. Smart contracts are systems that enable the movement of digital assets according to autocratic pre-specified rules. A reasonable extension for this is long-term smart contracts containing the assets and encoding the laws of an entire organisation, known as decentralised autonomous organisations (DAOs).
3.2 Smart Contracts in the Energy Industry
The “energy internet” topic was brought to light in 2018. Different authors investigated the application of blockchain technology in sustainable energy systems. This research signalled the criticality of overcoming the hurdles involved in controlling and managing distributed sustainable energy forms.
Energy as a service is a rising business model that enables the otherwise passive energy consumers to play an active role and participate in the energy utility services. This platform is formed through smart contracts registering peer-to-peer (P2P) energy transactions through price and quantity. Many industries, including finance, have already leveraged smart contracts to introduce digital currencies.
In terms of actual applications, virtual power plants (VPPs) represent a concrete implementation with challenges and opportunities. A VPP is an arrangement that integrates many types of power sources. The prime objective of a VPP is to give a reliable power supply; its sources are often a cluster of distributed generation schemes with intermittent renewable energies .
At this time, the utility industry is faced with how to structure smart contract formation in a local energy market. Specifically, they are faced with the challenge of maintaining a balance between energy generation and demand while enabling traceability, security, and unbiased peer-to-peer energy transactions, especially within a virtual power plant.
Blockchain applications in the energy sector can be seen in the following list:
- Metering, billing, and security
- Cryptocurrencies, tokens, and investments
- Decentralised energy trading
- Green certificates and carbon trading
- Grid management
- IoT, smart devices, automation, and asset management
- Electric e-mobility
- General-purpose initiatives developing underpinning technology
An outlook of the use of blockchain in power systems highlights tracing and trading of ancillary services provision (e.g. voltage and frequency regulations) as the application with the utmost potential. Plus, it states that electricity trading, tracing and certification, are the two types of applications where blockchain appears to contribute the most. Moreover, specialists focus on how effective blockchain becomes in the energy sector for integrating small devices into various markets specialised in ancillary services provision. In this sense, smart contracts can be used to model the complex governing structures of these markets.
Local energy markets (LEMs), or local peer-to-peer (P2P) markets within a physical microgrid, is where all members of the local community are located downstream of a transformer station and share the same voltage level. LEMs are viewed as a method to empower consumers and prosumers to trade locally produced energy. LEMs intend to overcome the traditional topdown approach of centralised management systems for grid control and coordination. This model leaves consumers and prosumers typically without a saying in determining the energy price.
LEMs need state-of-the-art secure ICT to harmonise local energy production and consumption, trading, near real-time pricing and balancing, aspects that blockchain can significantly achieve. It has been found that the bidding/selling prices of prosumers can largely incentivise the restructuring of prosumption behaviours in LEMs to attain regional energy balance and CO2 emissions mitigation .
Smart contracts assist in overcoming an indigenous LEM challenge; when prosumers perform P2P trading, it is challenging to ensure the settlement and delivery of any energy being traded without a standardised negotiation and execution procedure. Blockchain can set up decentralised trading platforms with automated trading operations and guaranteed residential privacy. Implementing replicable, tamper-proof, and auditable smart contracts allows the trading, negotiation and settlement to be trustworthy without the need of a trusted third party (TTP).
3.3 Smart Contract Design
Smart contracts allow a system to be independent, reliable, and autonomous for handling exchanges between the different actors involved. The proposed scheme of a smart contract is based on the consensus decisions about assembling the actors, as commented on previously.
In this framework, energy transactions use P2P decentralised tools to ensure that consumers and suppliers exchange energy directly, based on the protocol rules. These optimise the flow between the individual (considering the in-progress state of the system generation), demand, and prices. The actors need to sign a bond using a decentralised app to consent to the rules and participate in the exchange. These rules are derived from the optimal solution, unfolding the amount, price, and flow between consumers and suppliers.
Consequently, each time a new party appears in the system, the contracts must be recalculated and reconfirmed using the app. By doing so, the smart contract secures the right to participate in the system as a seller, a consumer, or both and incorporate an operation for assigning and updating transactions among peers and for accepting the terms and conditions stated in the contract.
4 ENERGY WEB CHAIN
4.1 The Case of EWC
As introduced before, the Energy Web Foundation is a non-profit willing to disrupt the analogue energy era. The Energy Web Chain is the world’s largest energy ledger ecosystem and has become the industry’s leading blockchain partner for grid operators, utilities, corporate energy buyers, renewable energy developers and others. And to their executives, it may even feel like EWC is uberizing or airbnbizing every single electric device on the planet. Part of this venture will be D3A — a decentralised energy marketplace.
Energy Web Ecosystem is embodied by some of the biggest companies in the world, such as E-On, Engie, Electrobas, Eneco, ECOHZ, etc. Validators that put financial resources and now host nodes for the chain include the huge energy companies EDF, Shell, Total, PTT or Tepco.
EWF picked a Proof of Authority (PoA) consensus mechanism, which means the validators of the chain are permissioned, hosted by the Fund’s affiliate organisations. But the blockchain itself is permissionless, so any user with a private key can use it without any limitation. The advantages of PoA application are high scalability, low energy consumption, and low transaction costs.
EWC is a foundational blockchain specific to the energy sector. Its Decentralised Operating System (EW-DOS) is an open-source stack of software, standards and software development toolkits (SDKs) running on the decentralised network certified by the well-known companies from the energy sector such as technology companies, large utilities, and grid operators. EW-DOS has three separate layers: the trust layer — provides the standard for the timestamp immutable data-sets and their state progression in smart contracts —, the utility layer — the middleware of the EW-DOS stack, providing codes and machines to quickly build solutions for UX tools, back-end application services and high-volume messaging — and the toolkit layer — software development engines for different usecases and markets, the two core ones are Energy Web Origin and Energy Web Flex .
There are plentiful possible usecases for Energy Web:
- Increasing grid flexibility by using DER or distributed energy resources;
- Empowering developers to build applications built on foundations of EW-DOS;
- Delivering energy attribute certificates (EACs) for proving that renewables such as wind, solar or hydro have generated a certain volume of electricity in a particular place at an exact moment;
- Simplifying traceability of carbon emissions.
4.2 D3A Energy Exchange
The D3A is an open-source energy exchange engine that enables users to model, simulate, and deploy an energy exchange in a local community either as a decentralised exchange or in a centralised fashion. The European Union’s Regulation on wholesale energy markets integrity and transparency defines an energy exchange as
“…a multilateral system operated and/or managed by a market operator, which brings together or facilitates the bringing together of multiple third-party buying and selling interests in wholesale energy products — in the system and following its non-discretionary rules — in a way that results in a contract, in respect of the wholesale energy products admitted to trading under its rules and/or systems.” 
Depending on the application, the D3A exchange can be operated by a single operator, a group of operators or be completely decentralised. If it is configured as a decentralised exchange, it could be based on smart contracts, which contain the market logic required to match or clear trades. This option eliminates conflict of interest in that all market participants enjoy the same market access. Bids and offers are supplied to the market based on device trading preferences and matched or cleared according to the smart contract, which could run on a decentralised blockchain-based platform, specifically the Energy Web Chain.
By opting to operate the D3A smart contracts on a blockchain platform, the D3A could facilitate the settlement of transactions in hierarchies without a centralised controller from the bottom up. This means that energy trades happen at the lowest layer first, such as inside a home, and then have the opportunity to buy or sell at the next layer up, such as between houses on a street.
These trades are stored on a public ledger, allowing for modular scaling of grids and plug and play interoperability in compliance with the relevant legislation. This means that different grid layers, organised by markets, can seamlessly connect and trade in the D3A structure. Hence, the D3A allows energy devices of arbitrary scale to deal with their peers on a scalable market platform resulting in local energy management and grid balancing.
The D3A exchange engine is available as open-source software under a General Public License (GPL GNU v.3) that allows free access and use as long as the final product is also open-source, with any modifications requiring permission and any closed-source product development requiring a license. In turn, the D3A user interface was created to allow users without programming skills to interface with the D3A exchange engine through a user-friendly web application, available as a beta version at https://www.d3a.io/.
Energy companies and consumer groups can use the D3A to:
- Model and simulate a market, thereby facilitating investment and other strategic business decisions;
- Deploy the D3A exchange engine to operate a decentralised and distributed smart grid efficiently.
The current energy world is dominated by oligopolies and intermediaries that govern power generation, energy consumption and trading of assets. Energy markets are predominantly operated on centralised exchanges not readily available for every citizen, thus creating a disparity of power.
Tokens bring a new approach to energy markets through decentralisation and democratisation by granting equal access to anyone with an internet connection. It is now possible to find many startups that enable fractional tokenisation of energy assets, focusing on ecosystem conservation, renewable energy, and clean technologies.
Digitising tangible assets is deemed to create universally accessible, transparent, and fast investment and financial systems. However, blockchain and related energy assets tokenisation are still in their infancy, and some obstacles need to be overcome before widespread adoption occurs.
Blockchain is mainly used in the energy sector for distributed energy systems, energy trading platform development, electric vehicle charging, carbon tracking, smart device connection, and energy provenance certificates. Local energy markets are able to integrate all of the subjects where blockchain is mainly being applied in the energy field and will therefore be the focus of this section.
The transition towards sustainable energy is characterised by decentralised renewable energy-based generation where traditional users are encouraged to become prosumers. The variability of decentralised and renewable energy resources puts the stability of the power grid at risk. Therefore, innovation in grid management architectures is necessary to orchestrate these decentralised resources.
Solar cells, electric vehicles, smart thermostats and even bitcoin mining facilities equipment will all be connected to the distributed Energy Web and start using traceable, verifiable clean energy.
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