What happens when the grid has excess energy?
What happens when the grid has a shortfall of energy?
How can home energy systems, contribute intelligently to grid in a more dynamic way?
Welcome to the future of energy in the UK, dynamic pricing, where prices fluctuate every 30 minutes, the more energy you can store, or give back, the less your likely to pay when it comes to the monthly bill… interested ?
In this article, we will address the developments coming, and already live in some parts of Europe allowing consumers to work alongside the grid in supporting a carbon neutral future.
- I was invited to a technical training session by Victron Energy, who have been creating energy systems since 1975. The company was founded, through an inventor who created a system that worked on Dutch shipping boats, allowing modern ‘240V’ appliances to run off the boats ‘24v’ battery systems present. Victron over the past 50 years have led the way in off and on-grid energy systems.
Brief Timeline
- In the past (2005-2015) homeowners had solar placed onto roofs. Energy generated that was needed by the property was consumed, and excess energy was fed back to the grid. The UK grid continued to burn fossil fuels to generate energy.
The graph illustrates the problem with this, as when the homeowner is unlikely to be at home, energy generation is at its peak, and when the homeowner needs the energy its being drawn from the grid, due to low generation. 4-7pm is the dirtiest hours for the grid, when the most fossil fuels are burnt.
- Along came battery storage, which integrates with home energy systems that seek to capture any excess energy the homeowner isn’t using and supply it when the homeowner requires, reducing the requirement of grid consumption. A simple energy meter is needed at the point where energy comes into the home, that communicates with the battery and inverter.
You can see the during peak generation in blue is stored in the battery to be used later in the day, excellent.
- As home energy systems developed further, customers with economy 7 tariffs, have been able to charge batteries (if they haven’t been charged enough by solar) from the grid at off peak hours at lower prices, and use this energy when prices are higher. Should the batteries be sized sufficiently, its theoretically possible, to charge enough to ensure the home almost never needs to draw energy from the grid when its price is high. Typically, 00:00am-07:00am would be at a low rate (7.5p per kWh May23 Octopus EV Rate) (when the grid demand is low/surplus) and the rates outside of this time are higher. Customers are having to manually look at future weather, in order to adjust whether to charge batteries at night or not, to avoid having full batteries and plentiful solar energy the next day.
- With the rapid growth in renewable energy for the grid, solar is generating during peak times (good) and wind turbines continue to spin in the right conditions for 24h a day. The fossil fuel powered grid is working hard, to power up and down generation stations to balance the energy supply & demand. This isn’t a perfect science or efficient, and there are delays and over provisions as part of this where energy must be shed. The grid has little if any battery storage at present on a mass scale.
How can the free market respond, in a way that can help the consumers achieve a lower price for their energy?
If the grid is able to push excess energy to consumers when it has too much of it and ask customers not to use or share energy when it doesn’t have enough of it, it would be immensely beneficial. If the system is efficient, at dealing with peak demands at busy moments, fewer, new power stations will be required, which further keeps costs down for energy customers, as our hunger for power hungry appliances continues.
- ESS (energy storage systems) that Victron offer do a great job of managing most of this. Having met their lead in R&D, he explained that in 2022 his energy bill was -£89. He was effectively being paid by the grid for his energy consumption in 2022, and his NET demand was positive. He used energy but didn’t have to pay anything for it. Quite remarkable.
So how did he achieve this?
- In the European Union there is a body called the ENTSOE. The local grid in Holland is trialling offering customers free or low cost energy when it has surplus, and even paying customers to take energy & charge batteries in these times, and at other times of energy shortfalls on the grid, paying customers to off load and push energy to the grid at a higher price.
- Victron is developing a system of Dynamic ESS, which will allow its customers to link their Victron Battery/Inverter systems to the grid, and through the Victron technology and an API link to the ENTSOE, manage the system in order to financially benefit from energy storage within the home. Whilst many homeowners with systems already have most of the components needed, they won’t be getting a dynamic rate for their energy, and only pushing back when they have surplus. It makes greater sense to push back when the rates are high, and charge dynamically when you are being paid for it.
The software for this application is freely available on github here : https://github.com/tfranssen/dynamic-ess
And a number of scenario’s are presented where you’d expect a system to respond:
I am excited about the benefits this can bring to all as part of the green energy transition and will keep our readers updated about its progress.
I understand Victron’s own Dynamic ESS system will be looking at the home’s energy consumption within the past 28 days, weather tables, and pricing in order to as efficiently as possible ‘place a bet’ on how much and when to charge batteries.
Existing Octopus energy customers can apply to be put onto the ‘Agile Octopus’ here https://octopus.energy/agile/
We will keep our readers updated on these latest developments.
