With the recent push to integrate renewable energy into the existing energy infrastructures, it is becoming clear that there is a need to adjust its operation mode. This need is apparent because most renewable energy sources depend on the weather and are not easy to predict or plan with. Moreover, the power generated from such sources as wind energy and solar energy is highly stochastic. This situation calls for the application of advanced technologies for renewable energy forecasting and scheduling.
Renewable energy forecasting helps foresee what changes are expected in the amount of energy that will be generated in the future. This prior knowledge is informative for energy suppliers to plan the input they put into generating systems. Renewable energy scheduling also works side-by-side with forecasting because it is mainly determined by the predictions made by the energy forecasting models.
How renewable energy forecasting and scheduling work
Recent advancements in artificial intelligence have improved the job of weather forecasting (done by meteorologists) through machine learning. As a result, grid operators can leverage machine learning techniques to determine the amount of renewable energy that will be used and purchased by consumers at a particular time.
Machine learning (which is used for renewable energy forecasting) works because a software system learns patterns from recent data and develops an improved analysis for the future. In order to achieve this, a forecasting model is designed to fit a particular situation over several days. In addition, the data collected must be valid, accurate, reliable, consistent, and complete to be effective.
What You Should Know About Renewable Energy Forecasting And Scheduling
Here are five important things about renewable energy forecasting and scheduling you should know;
1. Renewable energy forecasting is built around short-term forecasting
Forecasting can be done with different horizons: short, medium, and long-term. Short-term forecasting involves forecasting from a few minutes to a few days ahead. It is used for day-to-day activities, and this time frame applies to renewable energy prediction.
The lead times in short-term forecasting are such that the changes in weather over a short period can be analyzed and used to predict the data to be used the next time. Renewable energy forecasting and scheduling require updated and recent data as frequently as possible, and short-term forecasting achieves that. The amazing part of it all is that there would be little or no human interruption with the presence of technology. Such way, errors would be significantly minimized.
2. Decentralized computing plays a prominent role in renewable energy scheduling.
Decentralized computing involves the allocation of both software and hardware to various points of duty. It is not like centralized computing, where all activities stem from a particular place. This form of computing (decentralized computing) is necessary for renewable energy scheduling because of the nature of locations in renewable energy generation and consumption.
For example, in an energy community, several houses may produce power at a time, and some utilities need power. The allotment of power to different places can be done effectively with decentralized computing technologies like the blockchain. It is effective because control has to happen independently from various locations when forecasting predictions require an adjustment.
3. Smart grids allow for renewable energy forecasting and scheduling.
Smart grids are electrical distribution points that are not like the conventional grid. The difference is that they contain many operation and control systems, advanced metering systems, intelligent circuit breakers and boards, and most importantly, renewable energy sources fit in well. Their operations are more efficient and can be readily evaluated because of the availability of needed information at the click of the finger. It is in such a system that renewable energy forecasting and scheduling can thrive.
Advanced forecasting models can be introduced and used to plan how the plants would run, whether solar photovoltaics or wind turbines. The ease in integration occurs because the smart grid already has smart IoT devices for thermal sensing, smart meters, phasor management networks, and the likes.
4. Grids with renewable energy attain stability easier with forecasting models in place.
Grid stability is of utmost importance for the sake of the life span of grids. Grid operators cannot consistently have variations in input and output in the grid happen repeatedly. With accurate renewable energy forecasting models, proper preparation and scheduling would be done, and there would be less frequent stability problems. Renewable energy forecasting and scheduling cut back most excesses when it comes to grid management.
5. The weather is a significant factor in renewable energy forecasting and scheduling.
Renewable energy forecasts are usually a combination of accurate weather predictions and the availability of plants and systems. The weather is a great factor, as the weather changes cause significant changes in the renewable power generated. For example, the variable speed of the wind is proportional to the amount of power generated by wind turbines. In the same way, the intensity of sun rays and the positioning of clouds play a big role in the fluctuations when it comes to solar power.
What makes renewable energy forecasting and scheduling interesting is that it studies the highly influencing factors of effective power generation. This kind of study is immediately applied, rather than just being carried out for nothing. It turns out that analyzing the weather, as Meteomatics does, has a vital role in the forecasting done by Hive Power’s Forecaster.
Renewable Energy Forecasting and Scheduling Solution – Hive Power
Hive Power’s Forecaster is one of our Flexibility Operator’s modules that performs short-term forecasting in a very accurate manner. It simply considers various factors involved in renewable energy-based power generation and uses them in forecasting. Its machine learning models make predictions on the amount of energy that would be used and generated in the future, based on previous data. This data is real-time data which is very helpful because it is used as soon as it is delivered.
Renewable energy forecasting and scheduling are essential for the effectiveness of renewable energy systems. With more observations in the needs of a renewable energy system, new technologies keep springing up, and it fosters development. Therefore, it is crucial to embrace these technologies as they come, especially when they are practical and efficient like this (in renewable energy forecasting and scheduling).
One of the more popular analogies used in describing how important some responsibilities are compared to others always goes along with the words “those on the front lines”. In grid operations, these people are saddled with the enormous responsibility of maintaining the balance between input and output. Despite the advances in grid operations and a steady move towards a more self-reliant and sustainable energy sector, the need for trusted operators is still relevant.
What Does a Grid Operator do?
A Grid Operator or System Operator is a manager that ensures the “reliable delivery of electricity to consumers, businesses and industry”. They are the grid managers who track operations from a set of computer consoles within a control centre. They spend most of their time making sure all grid systems function at optimum capacity. The need to anticipate and mitigate situations that could become potentially dangerous or costly is also part of their work purview.
Working as a Grid Operator means constantly improving skills using simulations to practice new situations and guaranteeing that they can quickly respond and restore safe power conditions to the grid in the event of a systems failure.
How DERs are Changing the Scope for Grid Operators.
When it comes to expanding grid operations through new energy sources or distributed energy sources (DERs), there are four main aspects:
- Enabling technologies like utility-scale batteries, EV smart charging and renewable mini-grids
- Business models like peer-to-peer electricity trading and pay-as-you-go models
- Market design such as net billing schemes and innovative ancillary services
- System operations that include the future role of grid operators, virtual power lines and co-operation between transmission and distribution system operators
The future roles of grid operators will have to consider the increase in responsibilities that reflect the need to use a higher number of DERs in grid systems.
DERs are small or medium-sized electricity-producing resources or controllable loads that are connected to a local distribution system. They include distributed generation such as solar panels, small scale energy storage and controllable loads like EVs and demand response.
The conventional scenario of grid networks has mainly been centralised. Their organisation revolves around energy generation, transmission and distribution, with the consumers pinned at the end of the supply chain. In recent years this system has gradually morphed into something toeing the line of a form of decentralised energy distribution. Consumers are becoming part of the process of energy generation, transmission and distribution, leaving grid operators with less of a clear-cut series of responsibilities.
Emerging distributed energy resources (DERs) like rooftop solar photovoltaic installations, micro wind turbines, smart home appliances and plug-in electric vehicles are becoming quite active in the energy grid networks. Add this to the new market players such as prosumers, aggregators and more informed consumers, and the result is a new era with new opportunities.
So, for the energy transition to be successful, grid operators will have to develop new incentives, adjust their current roles and adapt their operations to accommodate these new DERs.
Becoming a Grid Operator of the Future – Emerging Roles For Grid Operators
As DERs keep penetrating the existing energy grid networks, the predictability of traditional planning, transmission, and distribution could be negatively affected, creating some blindsides. This is why the conventional roles of grid operators need to change.
We can sum up the conventional roles of grid operators in:
- Connection and disconnection of DERs
- Planning, maintenance and management of networks
- Management of supply outages
- Energy billing
However, these grid operators could have access to the flexibility of DER integration for the benefit of the distribution grid and consumers alike. Here are a few roles they could take up with proper adaptation:
- With an appropriate regulatory framework, the grid operators could begin operating DERs
- They could act as neutral market facilitators, providing high-end price signals to the market players who own flexible assets
- They could take on an active role in system operations in addition to their network operations roles, procuring flexibility services such as voltage support and congestion management
- They could be in charge of peak load management through DERs
- They could provide reactive power support to TSOs
Conventional roles still play a considerable part in sustaining grid networks. Integrating these new roles will help with much-needed regulations and increase economic advantages for asset holders.
Regulatory Mechanisms That Could Help
Most of these regulations are still in their early stages of development and are given as a guideline more than anything else.
Two of such regulations are:
- Connection agreements for end consumers that are not firm – These are connection agreements that state that DSOs will reduce network fees during peak hours if consumers agree to have constrained power supply during that period.
- Bilateral flexibility contracts – In this sense, DER owners and operators agree to provide local system services like voltage control to the grid operators.
The new Responsibilities and Their Impact
These new responsibilities will significantly affect how power grids operate in the future, and we can highlight some key benefits:
- Increasing flexibility in distribution networks – Through this, grid operators could get flexibility services from assets that are already connected to their distribution network. Using these services will further help the integration of renewables into the distribution network. One advantage of this benefit is the extra revenue stream it introduces with the help of incentives which further improves the flexibility of the distribution network.
- Using DERs to avoid or reduce network investments – This allows the grid operators to have numerous options at their disposal during peak demand periods or periods of network congestion. They can decide between reinforcing the grid, offering non-firm access to their consumers or use the flexibility services provided by the DERs.
- Leveraging data to increase renewable energy penetration – Here, grid operators can play the role of the consumer data manager, collecting and storing data related to electricity consumption, billing and location, as well as types of DERs. These can then be used to better forecast demand which would help with better planning and distribution.
The potential impacts of these changes are projected to be immense. Grid operators are not necessarily a defunct part of grid operations but will have to leverage the new and the old to create a working framework for future operations.
As the need for new phases in the power sector begins to unravel, no one can underplay the importance of fitting in. For a long while, grids have transmitted power, usually from non-renewable energy sources such as coal, oil, and natural gas. The production of this power is according to a scheduled and centralized system, so you would expect that it would achieve grid stability easily most of the time.
Unlike conventional grids that have synchronous generators to support their stability, grids with renewable energy sources require a lot more to attain stability in case of interruptions.
Understanding Grid Stability
It’s simple; there needs to be a balance in production and consumption within an electrical grid. For there to be stability, the energy generated must be equal to the energy consumed. So, “unreliable” energy sources don’t fare well with conventional grids.
For a power grid, to remain stable, it needs to respond to volatility in voltage and frequency disturbances. For example, suppose more power is generated than consumed or more energy consumed from the grid than generated. In that case, complete adjustments are necessary within an acceptable timeframe to balance the frequency disturbances and power outages. Equilibrium is what is most important.
Let’s Bring Renewable Energy Into The Picture.
According to the International Energy Agency (IEA) report, the renewable energy sector’s growth is set to skyrocket by a whopping 50% between 2019 and 2024. With solar photovoltaic energy leading the way, closely followed by wind and hydropower projects – which are gaining traction with speedy rollouts, the fastest observed in four years. This growth is happening because of the reduced costs of renewable energy technologies, global set targets and decarbonisation policies, and the increasingly high electricity demand.
In the production of power with solar energy, the fluctuations in the supply and demand of energy for a particular place can cause instability in the grids. These fluctuations occur because the sunlight intensity in an environment with homes using solar panels, for example, varies from time to time. Thus, while the transition to sustainable energy is still on, homes, offices, or general end users would still have times when there is low power generation from renewable energy sources. Also, there could be wastage when supply is abundant if grid operators do not apply adequate measures.
The wind turbines used to produce renewable energy are also doing a great job. Still, the fluctuations in power production pose a threat to the stability of the grids. These fluctuations come from the nature of wind speed in these applications.
Relying on renewable energy sources brings its share of challenges that need definitive solutions. These solutions can be storage options, handling fluctuations and specifications for particular RE sources; (for example, solar power solutions would differ, if not slightly, from solutions for thermal energy sources or hydropower, wind farms, and the rest).
What Are The Grid Stability Problems With Renewable Energy Sources?
The three major challenges faced by conventional grids when it comes to the adoption of renewable energy sources are:
1. Frequency and voltage anomalies
The stochastic nature of wind and solar energy production makes the frequency and voltage produced unreliable to an extent. Power inverters are supposed to adjust system fluctuations in solar power generation. However, they have proved to be weak in effectively carrying this out. In addition, the time of the day and the weather conditions continuously affect the production of power. These conditions seriously affect the operation of the grids, bringing them close to their limits.
2. Overloading of existing transmission lines
Due to increased loads during peak hours, the existing transmission lines face a challenge of capacities matching the inflow and outflow of power. A surge can occur when producers generate too much power without warning, and the entire system would shut down. A transmission line has its specified capacity, and if this limit gets passed, thermal loads will build up, leading to damage.
3. Demand and supply mismatch
As much as many homes, offices, and buildings need the power to run their operations, it cannot be at a time. The production of renewable energy can be very high at some points in time. But, also, it can be low under other conditions. Therefore, the power generated when it is needed may not be sufficient or may not match the demand.
How They Can Be Solved.
The issues faced by the grids with renewable energy sources are not unsurmountable. As challenges arise, new technologies that can effectively tackle these challenges start to present a solution. Distribution System Operators can regain grid stability by applying techniques and technology to ensure the effective adaptation of renewable energy in the power sector.
1. Use of energy storage technologies
Energy storage is a great way to tackle the grid stability issues with renewable energy. It does not stop at immobile lithium-ion batteries, but mobile batteries too. The use of ‘moving’ batteries involves energy storage along transmission lines and even in electric vehicles. Virtual transmission is one of the technologies that come into play concerning specially configured battery systems. They come to the rescue of congested transmission lines and help grids retain stability.
2. Implementation of Smart grids
Smart grids have many features working together intelligently. The most advantageous features that affect grid stability include the control and communication systems. In addition, the sensors can detect and evaluate imbalances in power distribution. This way, the equipment’s health is closely monitored. Thus, you can ensure grid stability with smart grids, and Hive Power provides the technologies needed for this implementation.
Grid managers always have to be on top of this growing problem of increased injections of renewables to the grid networks and tally these increases with their corresponding costs.
Also, operators can find solutions for grid stability issues and renewables in:
- Installing a huge number of reactive power compensation plants and building HVDC transmission lines from the generation centres to the load centres
- The use of conventional load flow controllers (however, these proved to be too slow when compared to the rate at which renewable energy use is growing)
- A dynamic load flow management system (which seems to be the best option) found in a unified power flow controller that can be fast-reacting. This solution should keep power lines within the n – 1 criterion balanced by managing both series and parallel compensation, which would keep the electricity on and flowing at optimum.
Hive Power – Smart Grid Stability Solution.
Our solution modules address the problems related to grid stability with AI-driven technologies put in place. For example, the Flexibility Orchestrator modules for grid operators provide grid analytics, manage flexibility, and optimize the distribution of power on their grids.
Some of the functions include:
- forecasting of energy data for power production and loads – this predicts how the production would go, based on previous operations, and the number of loads as well can be forecasted
- provision of analytics for the Advanced Metering Infrastructure (AMI) – Smart meters can measure the energy consumed per time, check power factors and give relevant data to the consumers and producers
- use of monitoring tools and overall visualization – generalized views give a bigger picture and allow for easy monitoring and detecting of faults or anomalies
- optimal grid management by the use of analytics – the entire grid processes and operations can be systematically organized when analytics interpret and communicate all data on the grid meaningfully
- preventive analysis of future grid violations – utilizing the data and analytics available on the grid, preventive measures can be derived and put in place to avoid breaches.