A beginners guide to energy flexibility
Updated: Oct 22, 2021
Here at KrakenFlex we control in real time a variety of Distributed Energy Resources (DERs) across a range of industries. In this series of posts by our engineering team, we will introduce the DERs we commonly control and the integration solutions we utilise. In this first post we will provide a general introduction to the broad range of asset types we integrate and the flexibility they provide Generation DER
Generation sites come as either “behind the meter” (BTM) or “in front of the meter” (FTM).
Behind the meter generation sites are those where the power generated can be used on site by an end user without passing through a meter. Examples of these would include a factory with a large solar array on the roof, or a data centre with on-site diesel generators. These sites can also export power to the grid, as long as the on-site generation power output exceeds their demand. Conversely “front of meter” systems require the energy to be passed through a meter before they are consumed by an end user. Typical examples of these would be large scale generation plants such as a windfarm or a gas generator powerplant.
The technologies discussed below can be either behind or in front of the meter.
Renewable Generation (Solar / Wind etc) These are the most obvious assets for which we provide flexibility, dispatching and curtailing their output depending on the mechanisms they are operating in and the market requirements at a given moment in time. Whilst solar and wind generators sites do not provide the same flexibility in being able to be switched on at will due to the nature of their energy sources, the ability to curtail renewable generation can be crucial to maintaining stability of the electrical network (and customers are paid to do so).
Examples of where this may be required could be where constraints on the grid mean generation cannot be supported for a given period of time or where the level of generation outstrips demand leading to a potential surplus of energy on the grid and potential instability. Gas/Diesel Generation The typical usage pattern for these assets is to provide “on demand” energy to the grid. These resources, unlike their weather fed siblings, can be turned off and on as required, and at great speed. This flexibility means they are well suited to provide reserve dispatch services as well as participating in the Balancing Mechanism (BM).
The sites providing these services are typically purpose built power generation sites, but increasing numbers of behind the meter customers are now looking into the opportunities their existing standby generation assets can provide. Demand DER Whilst we frequently read about the increasing penetration of distributed generation and low carbon technologies on the grid, it's quite easy just to focus on generation systems (Solar/Wind/Biomass etc.) but being able to shift load (demand) also provides flexibility to keep the grid stable alongside providing financial benefit to our customers. This is typically referred to as demand side response (DSR). These asset types can vary but commonly include HVAC (Heating, Ventilation and Air Conditioning) or large loads such as Heat Pumps (HP) used in conjunction with a thermal energy store or industrial processes that are flexible in their running arrangement. HVAC Loads
Heat Pumps are able to transfer thermal energy from one point to another using the refrigeration cycle. The sources of the thermal energy are typically air, ground or water sources. To be able to transfer thermal energy, heat pumps require electrical power.
Where there is flexibility in the thermal output, a form of demand side response can be provided. An example of this would be the ability to reduce the HP thermal output temporarily without adversely affecting the product. This can be further supported through the use of thermal stores. This is increasingly being utilised in agricultural processes including grain drying and potato storage.
Industrial Processes Similar to HVAC loads, where an industrial process is able to withstand loads being reduced, this flexibility allows customers to undertake DSR (Demand Side Response). Where a reduction of power to the customer from the grid is not feasible, the reduction in grid power can be supported by other generation assets so that the customer experiences no impact.
Battery Systems Considered as the future backbone of our electrical network moving forwards, these assets act as a buffer providing the best of both worlds, they can import power (act as a load) as well as export power (act as a generator) which in turn helps balance the grid.
These assets are able to operate in markets and mechanisms requiring fast acting responses such as Dynamic Firm Frequency Response and Dynamic Containment where the output of the batteries varies in line with grid frequency.
An increasing number of existing generation sites are now beginning to integrate these assets to provide greater flexibility in their offering and revenue streams by offering ancillary services such as frequency response.
The versatility of the KrakenFlex platform allows us to integrate our systems with a wide portfolio of assets. Working with our customers, we offer a number of integration solutions tailored to the type of asset they are looking to "flex". In our next post we will begin to explore the options...