Like roads, electricity networks have ‘rush hours’ where loading levels peak and capacity is fully utilised.
Orion's rush hours typically occur on cold winter mornings when residential load coincides with the start of the business day, and again on cold evenings when people arrive home from work and turn on their lights, heaters, and cook their evening meal. In our rural network peaks occur during summer months because of the large number of irrigation pumps connected to our network.
To see an overview of our current load levels, take a look at our load management dashboard.
One solution to cope with these relatively short periods of high loading is to expand our network's capacity - much like making roads bigger to handle more traffic. But this is very expensive, especially given that the additional capacity is not needed 98% of the time, and would mean price increases.
We think it makes better sense to promote other cheaper options, such as load management, where we reduce the electrical load on our network during periods of peak demand. We can do this by heating hot water cylinders at off-peak times, and through pricing that encourages off-peak electricity use.
We have a ripple signalling system that allows us to send signals through the electricity network to ripple receivers at customers’ premises that switch appliances like hot water cylinders on and off.
We provide a number of different signals to manage load in different ways:
our peak control signals are sent out only when they are needed - when load is peaking. We start switching the appliances back on as soon as load levels start to fall and we aim to keep the duration of control as short as possible to prevent any noticeable effects on customers' hot water supply
our fixed time control signals are sent out every day, turning appliances such as water cylinders and night store heaters on when our loading levels are always low. This fixed time control permanently shifts load away from the daytime periods when peaks occur
our pricing signals provide incentives that reward customers who lower the amount of electricity they consume during our high-priced peak period. We provide ripple signals to tell customers that it's a peak period so that they can reduce their load and reduce their charges – this arrangement is more useful for larger business connections with special half-hour interval metering that records the reduced loading level during the peak period. We operate a separate set of pricing signals for our major customers and many of these customers lower their load, and use backup generation, to lower their electricity charges during our high-priced peak loading periods.
Ripple receivers are usually installed to take advantage of the cheaper pricing plans that are available, and, for electric water heating, it’s mandatory to have one. For more information about ripple control:
for customers, see our Ripple control option summary
for metering contractors, see our Ripple control technical summary
for electricians and plumbers, see our Ripple control tradesperson summary
for full technical details on the use of our ripple signals, including a schedule of our current switching times for night load switching, see our Ripple signal guide.