Energy management has not traditionally been the significant driver in the home automation sector, but this is beginning to change.

Until recently, home automation systems have only been seen in multi-dwelling affluent apartments/penthouses and multi-million dollar residences, where the focus has been on comfort, convenience and luxury. However, as environmental awareness grows, and the attainability of home automation progressively filters down into the mainstream residential market, energy management is increasingly taking a higher priority.

Many high-end homes and apartments might never be considered ‘green’, due to the physical size of the dwelling and the proportionally high reliance on power. Nevertheless, smart control systems do provide considerable scope for improving the way in which energy use is managed, and deliver the best balance between luxury and green agendas.

Energy balance
In general, heating and cooling make up the largest energy demands for most homes, followed by hot water systems and pool pumps. Lighting requirements contribute a relatively low percentage of the overall energy requirements. However, to achieve a fully integrated control solution, lighting control systems efficiently manage heating/cooling services in harmony with natural and artificial lighting.

This can be achieved using ‘occupancy detection’ and ‘scheduled events’ – through the use of sensors and time-clocks – for automating different functions at set times throughout the day.

For example, time-clock functionality can allow blinds to track the sun throughout the day and through the seasons.

This can effectively limit the unwanted heating effects from solar radiation at specific times of day for different areas – thereby reducing the need for cooling. However, closing blinds will also reduce the lux levels within the home, and this may necessitate the increased use of artificial lighting. As ambient light levels fall, light-level sensors can be used – via a control system – to gradually boost artificial lighting to balance the dimming effects of shading.

From an energy balance standpoint, the energy ‘wasted’ through the use of artificial lighting will invariably be offset by the greater energy ‘gains’ achieved by preventing unwanted heating of the home. Moreover, blinds/curtains can also be integrated directly with heating/cooling systems, such that they are drawn automatically in certain areas if the air-conditioning is activated. Again, this can help minimise the energy required for cooling.

Factoring in flexibility
Where a single predetermined setting will often suffice for automation systems in commercial settings, residential systems frequently require a greater number of control scenarios to correspond with the many ways a given area may be used. Usability is a key requirement, and user-overrides are a fundamental prerequisite to ensure occupant acceptance.

However, energy management performance can still be retained by programming the system to ‘lapse’ back to energy-saving default settings when areas have been unoccupied for a certain length of time. This can be achieved through the application of presence sensors, using a combination of motion and heat detection. Conversely, presence sensors can also be employed to activate preset automated scenes – incorporating lighting, cooling, heating and AV systems – when a space is re-occupied.

In the high-end residential sector, where comfort is often rated more highly than energy expenditure, user focus may not always be on the state of lighting, heating/cooling or entertainment systems while a property is vacated. For convenience and ambience on their return, remote-access capabilities – through the use of smart phones – can work well with home automation systems in an energy-conscious manner. A user is more likely to accept default settings that turn off heating, cooling and lighting when areas are unoccupied, if a system can be remotely turned on when they are on their way home.

Saving measures
As a general rule, in order to reduce power consumption, it is essential to be able to monitor how much energy is being used. Studies in the USA have shown that, on average, homes that are able to monitor their energy use consume 15% less than those that cannot measure their usage. With the roll-out of smart meters, users are set to be better able to measure usage in the future, and thereby minimise unnecessary energy expenditure.

There is a vast scope for energy-measurement functionality to be integrated with home automation systems, and this can be leveraged to both save and manage energy use more effectively. With the possible future introduction of time-of-day tariffs, home automation systems can help load-shift non-essential activities, such as electrically operated pool cleaners, to non-peak times. While not achieving actual energy savings, this can still provide considerable cost advantages to the homeowner.

Furthermore, the growth in on-site residential renewable solar electricity generation provides many opportunities to integrate energy-saving initiatives with home automation systems. Not only can renewables contribute massively to the environmental performance of a property, but they can also be used as a trade-off for other heating and lighting options. For example, if solar power is being generated on-site, this can justify the use of less-efficient luminaires that provide a better ambience.

Of course, to leverage the best results from any home automation system—and especially those incorporating sophisticated integration with other systems—the importance of using trained installers and programmers cannot be overestimated. Just as a modern car engine requires advanced diagnostics systems to realise the best performance and fuel economy, so a state-of-the-art home automation system requires careful initialisation by reputable integrators to ensure the best balance between comfort, convenience and energy management is achieved.

With home automation systems becoming increasingly affordable to the mainstream market, and with energy prices and environmental awareness continuing to increase, energy management has never been more important. Home automation systems can provide the means for homeowners to measure their energy usage, and develop effective management strategies to minimise it. No longer necessarily facing a trade-off between comfort and efficiency, today’s homeowner can now enjoy the luxuries of home automation in an ever-more energy-responsible environment.