Energia Juhtimiskeskus is an electricity consumption aggregator in the Baltic Countries
- What is demand side response exactly?
- Common methods of energy management
- Examples for energy management
- Main terms which are used in energy management
- Example devices for energy management
- Who else needs an energy management system?
Usually, consumers are not aware of how much they should deal with energy efficiency of electricity consumption. It is not known what possibilities there are or how much the company could save or money can be earned. In the companies often a central automation system is missing which could help to better regulate and control the consumption.
We have experienced that consumers do not know that the electricity production prices can vary significantly within a day and load shifting strategy is not used to lower the electricity costs.
Often it happens that there are no answers to those questions:
- How much do we save now?
- How much from what base do we exactly save?
- Do we spent a lot of time and money?
- How long is the payback?
- Have we achieved the maximum savings?
- Where else can we save and how much?
For our cooperation partners we deal with the optimisation of their consumption, they know the answers to these questions and much more. They are on the next higher level of electricity consumption awareness. Together we manage the electricity consumption intelligently and profitably. They have an advantage against their competitors.
What is demand response exactly?
Demand response is a change of the normal daily pattern of electricity consumption due to changing external influencers. Influencers maybe for example the electricity market price, consumption reduction for receiving revenue or if the security of the electricity system is in danger.
AS Elering is responsible for the security of the Estonian electricity system. In addition to Elering electricity producers and network operators such as Elektrilevi and Imatra Elekter are interested in lowering the peak load curve. Their interest is to reduce the need for additional electricity generating capacity, because it is very expensive and additionally increases the capacity of electricity networks. Furthermore the companies are interested in increasing the power consumption during periods of minimum load in order to reduce the overall costs of electricity generation.
If from the system side “incentives” are offered to consumers to exceed the potential costs for consumers to change consumption, the consumers are willing to change their usual consumption pattern. As demand response also gives an overall benefit to the society as a whole, thanks to the reduction of power supply and the minimised damage of nature from the electricity production, it is also interesting for the state.
Example: A single factory agrees to switch off the not vital equipment of their core business. In doing so it will set free a significant amount of electrical energy which can be used for example by households, hospitals, office buildings or stores. In return, the factory gets paid for not consuming electrical energy by the remaining amount of the fee, which makes the participation in switching off a benefit for the factory owner.
In short – the demand response is a change of the everyday energy consumption motivated by various inputs.
Typically, the desired initial demand response program includes aggregates which are non-crucial like lighting, elevators, pumps, motors, compressors, refrigeration and cooling devices which running time can be changed relatively easily.
Common demand respond methods:
Energy saving – for the aim of reducing the amount of consumed electricity and the electricity bill.
Peak load cutting – is designed to reduce the burden in the short term, the peak load periods. The change of the overall consumption is small, however, this may not be the goal. The tips of the reduction is achieved by a variety of load management measures, interruption of eligible consumers, own production, price policy.
Filling the hollow – increasing the load at load minimum hours of to achieve better usage of own generating capacity. Usually used in conjunction with peak load cutting.
The load-shifting – shifting consumption from expensive to cheaper times. Affects well the whole electricity system and creates savings for the consumer.
Switching Power sources – is helpful appliance, if there is an own production plant, back up generators, battery stations, etc., to reduce the payback period of investments and to maximise the income and the savings with already existing equipment.
Demand response examples
Below is the list of the simplest and most common examples of demand response applications:
- Switching off the hot water boiler for a few hours;
- Switching off or reducing the heating for a shorter or longer period of time;
- Switching the air Conditioning cycle on and off;
- Load limiters to limit the maximum consumption of the application;
- Using the short term advantage of the inertia of refrigeration equipment for short-term
- Short-term shutdown of pumps;
- Back-up generators and alternative power sources for exploitation;
- To shut down the production for a short period of time;
- To shut down ventilation system for a short period;
Key terms used
If you do not deal with power issues on a daily basis, some of the terms seem confusing or complicated. We want everything to be understandable and possibly simple and we explain below key terms that are used within the demand response field:
Consumption graph – shows the electricity consumption amount and time schedule, where you can see how much electricity is used for a certain time period. Typically, consumers have an existing access to the consumption graphics which measurement accuracy is 1 hour.
Base consumption (line) – is the normal pattern of daily consumption, where no demand response has been implemented. The base consumption needs to be known in order to measure how much of the company’s consumption can be reduced at the moment. This will be taken for the calculation for similar days consumption graph, where is no regulation compared to days where regulation occurred. So the received difference is known. According to this, you can calculate the savings, price advantages, income, etc.
Interval meters – measures and records how much electricity a customer has consumed in short term or intervals. In Estonia the interval length is 1 hour.
Kilowatt, megawatt – These units are necessary to measure power. 1 Kilowatt (KW) is equal to 1000 watt (W); Megawatt (MW) is equal to a million watt; Gigawatt (GW) equals 1,000 MW; The total annual electricity consumption of Estonia is approximately 8,5TWh (Terawatt-hours).
The kilowatt-hour (kWh), megawatt-hour (MWh) – these measured units are energy consumption. A 100W bulb consumes 0.1 kilowatt-hours per hour. Electricity Sellers submit invoices in MWh or kWh depending on the consumption size.
Load – the real amount of electricity energy in every moment which the consumer consumes is called its consumption load.
The peak load – the maximum amount of electrical energy that is consumed in a given time period. For example in a month, a week, a day or an hour. Every electricity producer must plan its activities so that it meets its own system peak demand at any time. Good if the peak demand meets correctly predicted prognosis.
Example devices for demand response.
To have the demand respond system working properly and comfortably, there is a need to install a device that receives and sends signals to the control centre.
For example in an office building is a device that is connected to the building BMS (Building Management System), it receives a signal from the control centre to turn off the cooling system and one third of the lifts. According to previously agreed rules the elevator can be turned off for 60 minutes and the cooling devices for 15 minutes. The signal for switching off and on comes and goes automatically. The consumer can, if necessary, end the shut-off as well.
It is possible to follow up the lifts and cooling system’s consumption graph in real-time or afterwards.
Result: None of the people working in the building noticed the shut-off of the lift and cooling device. Energia Juhtimiskeskus pays the office building’s owner for the not used load. Energia Juhtimiskeskus’s fee is a percentage of the saved and earned income. If there is no benefit there are no costs for the office building.
Who else needs a demand response system?
Energy consumption management’s demand response program is also useful in a wider social sense. Our parents, friends, our self, etc. receive lower grid fees for our homes, too. Thanks to the program very expensive new power plants are avoided and additionally it reduces the need for investment in the strengthening of the electricity grid especially in areas where problems exist or where consumption growth is very fast. Any investment in the electricity grid is paid by the consumers. The less unnecessary and avoidable costs, the less we have to pay.
Demand Response program also affects the overall electricity price in Estonia. Prices in the market are becoming more affordable thanks to the consumption reduction within the grid and it is possible to prevent very expensive power producers to access the electricity market and to avoid the increasing number of such deals as 150-2000 € / MWh, which we have previously experienced.
The demand side program also reduces the cost of balancing energy which must be paid for these consumers who have not entered any electricity contract. The balancing energy price decreases as the demand response program allows to manage the power imbalance which is cheaper than the alternative options.
Different other benefits are for example factors such as:
- the more complete electricity market
- lower market price volatility
- greater security for extreme situations
- consumers’ bigger control over their costs