In three-quarters of the participating households, we have implemented an automated system in which Linear switches on the equipment. Linear does this when there is a need for it: in case of a surplus of energy or an imbalance in the power grid, when the cost of energy is lower. The device continues to monitor the comfort level inside the household.
The best way to explain this in practical terms is by way of an example:
A test family wants their dishes to be clean for the evening. They turn on their machine at 8:00 in the morning and set the deadline for 6:00 in the evening, the time at which they want to use the clean dishes. The machine takes two hours to wash the dishes, so it has to start by 4:00 p.m. at the latest. This results in a time window between 8:00 a.m. and 4:00 p.m or 8 hours of flexibility within which Linear can start the machine remotely. If the machine still hasn’t started by 4:00 p.m., it will switch itself on automatically so that the family will have clean dishes by 6:00 p.m. This is an example of an implementation of automated demand-side management by Linear.
> find out how we configure the Linear equipment flexibly
Obviously this can only work if the energy supplier is able to communicate with the devices of the consumer. To do this, we use smart devices. We are studying the best time and the best criteria for switching on the machine according to four business cases.
The time window in which Linear can start the equipment is referred to as ‘flexibility’. Linear participants that provide a high degree of flexibility can earn an incentive.
Linear combines this automated control with rate control: when the devices are switched on, lower rates will apply. This is aimed at allowing the consumer to benefit from automated demand-side management as well.
The best-known and oldest-running example of rate control in the energy sector is that of the day/night rate. To avoid having to generate a highly disproportionate level of energy during the day (heavy demand) as compared to night (very little demand), producers make use of lower rates during the night. This encourages customers to shift their energy consumption from daytime to night-time when possible.
Changing sources of energy, unpredictable generation levels
Until a few years ago, energy generated from traditional sources was relatively stable, with most disparities occurring only between summer and winter. Due to the increased use of renewable energy sources, generation has become quite volatile, and this has led to unpredictable surpluses: on weekend days when the sun shines brightly for instance, if there are heavy winds during the night, etc. As with night rates, this can result in a lower energy price, but these swings are not as easy to predict as the difference in the day/night rate.
Variable rate control
Previous European projects have shown that unpredictable variable rates have only a minimal effect on usage patterns. This is why Linear employs this concept (with no automated control) with only a quarter of the project participants. The members of these test households have a display on which they can view six rate categories per day, with prices varying from day to day based on the projected levels of sun, wind, supply and demand. But with most participants, we are studying the effects of smart devices.
Time of use
We divide the day into six fixed time intervals based on the ‘time of use’ concept. Each day we determine the energy rate for the following day based on the amount of solar and wind energy that is generated as well as projected consumption levels. This is aimed at encouraging participants to use this detailed rate structure to schedule their electricity consumption during the cheaper time intervals and save money in the process. It also gives them an easy way to track their overall energy consumption and adjust it as needed.
Over the past several years there has been pressure from Europe to introduce Smart Metering and Invoicing, in which the price of energy varies depending on the time and the variations and is passed on to the end consumer. The goal is to encourage customers to shift their energy consumption to periods in which the supplier can provide energy at a lower cost. This also smooths out the peaks in consumption so that fewer peak power plants are required.