Demand Response
Emission - Economic - Security
The energy industry is moving fast. As older, polluting power stations are replaced by varying renewables, the UK industry needs an economic, efficient way to keep the lights on.
Demand response is the answer to the energy trilemma. As part of a diverse energy economy, demand response reduces emissions, saves money and helps secure electricity supplies [1].
Balancing supply and demand
Electricity consumers don’t ask permission every time they turn on a light. Large power stations can fail suddenly, and wind turbines only generate when there’s wind. So National Grid must always have something in reserve to keep the electricity system in perfect balance.
A large volume of reserve comes from part-loaded fossil-fueled power stations, even though it is inefficient to burn gas or coal at part load. Additional reserve is provided by warming older power stations, which can take twelve hours or more. Often, this reserve is not used in the end.
Demand-side flexibility
It’s more efficient for electricity users and small generators to provide some of the flexibility that National Grid needs. No fuel is burned when a standby or CHP generator, or a flexible load, is waiting to be called upon. When they’re needed, It can activate these demand-side resources very quicky.
Providing low-carbon reserve
The monitors the status of clients’ equipment from its control room. If a national demand peak is higher than expected, or if a large power station or interconnector fails, Then, received an electronic instruction from National Grid. The central control system then communicates directly with customers’ equipment through a outstation located on each site. This starts generation or turns down consumption within minutes or, in some cases, seconds.
Fit for purpose
With the most diverse portfolio in the industry, The national grid can apply different demand-side resources to the roles in which they will do the most good and earn the best returns.
CHP generators generally have periods of scheduled running. Outside those periods, they are a low-cost source of demand response. Like flexible load, CHP is activated frequently. Standby generators are used much less, targeting the most severe energy shortage situations.
Frequency Response
To make sure there is sufficient generation and demand held in readiness to manage all credible circumstances that might result in frequency variations. System frequency is a continuously changing variable that is determined and controlled by the second-by-second (real time) balance between system demand and total generation. If demand is greater than generation, the frequency falls while if generation is greater than demand, the frequency rises [2].
There are two categories of frequency response : FFR Static and FFR Dynaimic
Firm Frequency Response (Static)
Static Firm Frequency Response (FFR) is triggered when grid frequency drops below a specific threshold (49.7Hz). Participating in Static FFR provides you with the potential to create additional revenue from structured fees in the form of both availability and nomination payments.
Firm Frequency Response (Dynamic)
Dynamic Firm Frequency Response (FFR) is where continuous rapid response is delivered for all frequency variations within the normal grid operating range of 49.5 to 50.5 Hz, to help keep the electricity system within a target frequency. Participating in Dynamic FFR provides you with the potential to create additional revenue from structured fees in the form of availability and nomination payments.
Access STOR
Participating in National Grid's Short Term Operating Reserve (STOR) scheme delivers the potential to create additional revenue from structured fees in the form of both availability and utilisation payments.
Capacity Market
The Capacity Market (CM) aims to ensure there is sufficient capacity during times of network stress by making a monthly £/MW payment to participants who make capacity available to National Grid. When the margin between generation and demand gets tight, a Capacity Market notice will be issued by National Grid and, if a stress event (a national shortage of generation resources) looks likely, we will instruct you to respond.
The load shifting
Load shifting is not a new concept, and has been implemented successfully by industrial and commercial sites for years. But for those new to energy management, or in a role that covers far more than just energy optimisation [3].
what is load shifting?
Load shifting essentially moves electricity consumption from one time period to another. For example, postponing an industrial process to another time. The idea is that by shifting the load to another time, the returns generated through energy cost savings or DSR participation are greater than the loss of production.
Unlike many energy cost saving strategies, load shifting tackles the “when” rather than the “how much” conundrum.
How does it work?
Every plant has a certain amount of margin built into the controls to allow for failure or maintenance. With the right technology in place, this margin can also be used for controlled load shifting. This margin is also referred to as energy flexibility.
Load shifting can be achieved through rescheduling processes, turning on a site’s embedded generation or turning off unnecessary equipment and machinery. Load shifting does not result in a reduction in net quantity of energy used.
Why is the important?
The energy mix is more dynamic and diverse than ever. The 3 core goals for the grid is to decarbonise, decentralise and digitalise the electricity system. This has meant that more renewable sources of energy are available now than there has ever been, and it continues to grow. Not only that, wind and solar plants are dispersed across hundreds of miles of land and sea, feeding into different distribution networks. This creates a certain level of uncertainty in terms of both supply stability and cost stability too.
Load shifting enables businesses to do the following:
Energy storage for peak load shifting
The majority of industrial and commercial sites will not operate constantly. In this case, energy demand only rises during operational hours. Charging a commercial battery during non-peak times and discharging it during the operational hours means peak demand charges can be significantly reduced. Energy storage solutions also enable electricity from embedded generation to be stored and used at peak times.
Energy neutrality
Load shifting sequences are generally energy neutral. As we said earlier, load shifting does not result in a reduction in net quantity of energy used. Whilst load shifting can help end-users reduce their total demand charges, it may not necessarily reduce overall usage charges. If the postponed production is to take place, it will still require a certain amount of electricity.
This is not to say that load shifting isn’t still good for sustainability. If load is shifted to participate in a frequency response event, the business is still helping the grid to integrate intermittent renewable energy and thus reducing reliance on carbon-based power plants.
Load shifting in action
Load shifting is best practiced when connected to an intelligent energy platform. GridBeyond’s technology enables automated load-shifting, whilst analysing how best to place your energy flexibility in the market, whether that’s in the frequency response market, energy trading, peak avoidance or otherwise. This is worked out based on the best possible returns, to ensure the cost of shifting the electricity consumption is always exceeded by the financial returns, whether that’s savings or revenues.
- Participate in balancing services, such as frequency response
- Trade generated electricity at times of price peaks
- Avoid peak demand all together, such as DUoS and Triads
- When referring to load shifting in the context of cost reductions,
it is often also referred to as peak-shaving
References
[1]. Flexitricity Company (2020). Electrical Company [online].
Available from: https://www.flexitricity.com/ [Accessed 25 Apr 2020]
[2]. Energy HQ Company (2020). Electrical Company [online].
Available from: https://energy-hq.co.uk/products-and-solutions/demand-management-asset-flexibility/demand-side-response/ [Accessed 25 Apr 2020]
2]. National Grid ESO Company (2020). Electrical Company [online].
Available from: https://www.nationalgrideso.com/ [Accessed 25 Apr 2020]