The transition to renewable generation has been a cornerstone of modern sustainability efforts. Many businesses have embraced this shift by installing solar panels, wind turbines, or other renewable energy systems. However, this adoption can sometimes lead to a scenario where a business generates more electricity than it consumes, creating challenges in managing the excess energy. This article explores the causes of this surplus generation, potential solutions, and the technologies involved.
Causes of Excess Renewable Generation
Overgeneration on Weekends: Businesses often have lower energy consumption on weekends or holidays. For instance, a factory equipped with solar panels might generate significant electricity on a sunny Sunday when operations are minimal, leading to surplus power.
Nighttime Wind Generation: Wind turbines can produce large amounts of electricity overnight when business activities are low. This can result in an excess of energy with no immediate load to consume it.
Primary Solution: Exporting to the Grid
Ideally, the first line of defence against excess generation is exporting surplus electricity to the grid. However, many businesses face limitations with this approach due to grid capacity constraints or regulatory restrictions that prohibit or limit the amount of electricity they can export. In such cases, businesses need to find alternative methods to balance their generation and consumption.
G100 Relay System
The G100 relay system is a technology designed to manage the export of electricity to the grid. It helps in regulating the amount of power a business can export by monitoring the grid conditions and adjusting the export levels accordingly. When the grid cannot accommodate more power, the G100 relay restricts the export, ensuring compliance with grid operator regulations. However, if grid export is not an option, businesses must look for other solutions.
On-Site Generation Management
Adjusting Generation to Match Load: This involves modulating the renewable energy systems to produce only as much power as needed. Achieving this balance requires sophisticated control systems that can dynamically adjust generation based on real-time load and grid conditions. This method is complex and may not always be feasible, particularly for solar and wind systems that rely on uncontrollable natural resources.
Adding Dump Loads: Businesses can install dump loads to absorb the excess electricity. These can be:
Water Heating Systems: These systems can use surplus electricity to heat water for building heating or hot water supply. However, the capacity of these systems is limited, and they can quickly reach maximum temperature, requiring the system to shut off.
Load Bank Resistors: These are variable resistors that can be adjusted to absorb the excess electricity. While effective, this method essentially wastes the surplus energy, as it is converted into heat and dissipated without serving a productive purpose.
Battery Storage Systems: A more advanced and expensive solution involves installing on-site battery storage. Batteries can store surplus electricity generated during low-demand periods and release it during peak demand times, typically on a 24-hour cycle. While this solution maximizes the utility of the generated power, it involves high initial costs and ongoing maintenance.
Control Systems for Optimal Management
To effectively manage excess renewable generation, businesses should employ advanced control systems that monitor all aspects of their energy usage and generation. These systems can decide in real-time which generation sources to adjust, which loads to switch on or off, and when to charge or discharge batteries. A well-integrated control system ensures that the business operates efficiently, minimizes waste, and stays within regulatory limits.
Conclusion
Excess renewable generation can be a challenge for businesses, especially when grid export options are limited. While reducing on-site generation and adding dump loads provide immediate relief, they may not be the most efficient long-term solutions. On-site battery storage, although costly, offers a more sustainable approach by storing surplus electricity for future use. Ultimately, the ability to export back to the grid remains the best solution, emphasizing the need for businesses and policymakers to work together to enhance grid infrastructure and regulations to accommodate the growing adoption of renewable generation.
Bryce Energy Services combines practical energy and carbon consultancy with the CO₂ Impact online platform, helping businesses measure their emissions, meet reporting requirements and turn carbon data into achievable reduction projects.
With CO₂ Impact, your business can:
Calculate Scope 1, 2 and 3 emissions
Produce credible carbon reports and Carbon Reduction Plans
Monitor energy, emissions and progress year by year
Identify and manage practical carbon-reduction projects
Build an evidence-based route towards net zero
Unlike a standalone carbon calculator, we can help you interpret the results, investigate energy-saving opportunities and prioritise projects based on cost, carbon savings and practical deliverability.
CO₂ Impact subscriptions start from £29 per month.
Measure - Manage - Reduce - Offset - Report
Bryce Energy Services combines practical energy and carbon consultancy with the CO₂ Impact online platform, helping businesses measure their emissions, meet reporting requirements and turn carbon data into achievable reduction projects.
With CO₂ Impact, your business can:
Unlike a standalone carbon calculator, we can help you interpret the results, investigate energy-saving opportunities and prioritise projects based on cost, carbon savings and practical deliverability.
CO₂ Impact subscriptions start from £29 per month.