Li-Fi and Internet of Things (IoT)

NWAS is one of ten ambulance trusts in England, covering the northwest region with 104 ambulance stations. It provides emergency ambulance response via the 999 system and operates the NHS 111 advice service for North West England.

This innovative trial tested if utilising Li-Fi technology along with connected Internet of Things (IoT) devices can foster operational efficiencies in the trust’s day to day activities and reduce overall energy usage, helping the trust achieve sustainability goals.

This trial shows that Li-Fi device senor technology is currently not mature enough to be recommended for wider use in the NHS. This case study explains why going into detail of the lessons learnt implementing this technology.

Ambulance trusts face challenges due to their very large geographical area and numerous sites. Unlike acute hospitals, they must ensure connectivity deployments offer value across diverse locations, situations, teams, and ways of working. 

This makes large deployments and changes a complex process, where searching for operational efficiency is a constant priority when even small improvements are compounded into big benefits by the number of sites (and staff) effected.

As a result, NWAS’ IT teams are always on the lookout for ways to make the day-to-day tasks their staff face more efficient. This includes duties such as stock management, equipment audits, temperature monitoring, and waste disposal any improvement to these administrative tasks will improve the overall efficiency and accuracy of clinical work.

Whilst there are a variety of wirelessly connected devices that the trust is exploring to assist with these tasks, they have also identified that there also is a need for a connectivity method that allows personal devices to communicate information and facilitate.

Considering the trust’s responsibilities, any solution needs to be:

• efficient, reliable and secure with a wide range of clinical use cases, including possible future application in ambulances and other mobile vehicles
• capable of automating parts of many difficult, repetitive and onerous tasks
• able to realise a good financial return on investment in addition to the above efficiency savings

The trust trialled two initiatives simultaneously: Internet of Things (IoT) devices, and a designated area using Li-Fi technology.

Li-Fi is a wireless communication technology that uses light to transmit data and position between devices, unlike Wi-Fi which uses radio frequency.

In the example above, a device has a transmitter and receiver that can send and receive light modulations to communicate with an LED light fitting. The trust looked to use a Power over Ethernet (PoE) lighting design that will form the main device access points in their Li-Fi solution.

Another difference is in the practical application of each technology. As a far more established transmission method, Wi-Fi availability means that many devices have dongles and signal receiving technology built in, whereas utilising Li-Fi will require an external dongle and maintaining line of sight to the access point. 

In addition, the trust had to be aware of the conditions in which the solution is being trialled. Despite working in daylight, other lighting factors could impede the effectiveness of the connection. 

The benefits of using a Li-Fi solution focus on the reliability, speed and security of the technology as a data transmission method. As the data is transmitted by light, it avoids wireless signal congestion that can occur when utilising many Wi-Fi devices in the same space, as well as offering a very low latency to connected devices. 

The trust chose to test this new solution at their Chester Ambulance station. This involves strategically placing access points to act as data transmitters and enabling seamless communication with USB dongles on compatible devices including desktop, laptop and mobile devices. 

Li-Fi is an emerging technology and as such the trust found that current commercial offerings are limited, pushing NWAS to consider a smaller scale test of this new connectivity method. 

As a result of these availability restrictions, the scope for the Li-Fi deployment was limited to one meeting room, to explore the potential of the technology in a controlled, “proof of concept” environment. 
Alongside this Li-Fi deployment, the trust installed a variety of Wi-Fi enabled IoT devices, including:

• bin level monitors
• water leak detector.
• temperature and humidity monitors
• wellbeing and air quality sensors
• power over Ethernet (PoE) lighting to monitor and control new LED light fixtures 

The trust anticipated many benefits from the use of IoT devices alongside the proof of concept of Li-Fi connectivity:

• reduction in energy usage, helping the trust meet sustainability targets
• lower operating costs means that the solution is expected to pay for itself within 4 years of deployment.
• improved staff perception around connectivity and a lower number of connectivity issues logged.
• circumventing connectivity issues such as electromagnetic interference (common in busy ambulance stations).
• reduction in time spent on manual tasks via IoT devices 
• improved efficiency in collection of clinical/non-clinical waste.
• reduction in audit processes through automation.
• freeing up radio frequencies otherwise used by Wi-Fi

The two main workstreams of this trial will show how IoT devices can assist in busy clinical settings, as well as provide an early exploration of Li-Fi in a practical setting. Here, the trial can also let us compare a more usual connectivity method in the IoT devices, with a newly emerging one in the Li-Fi meeting room.

The trial deployed in September 2024, with IoT devices (including PoE lighting) being placed in twelve areas of the station, and Li-Fi sensors installed in one meeting room.

Pictured is a breakdown of the deployment system topology, showing the IoT sensors and PoE lighting working alongside the Li-Fi access points, and a reference device that connects to the usual station Wi-Fi.

The deployment underwent some minor adjustments due to the age of the ambulance station, and the availability of Li-Fi amongst suppliers. 

Li-Fi is a new technology with a variety of use cases, but as a result there are few suppliers who can deliver the solution for testing/implementing. Therefore, there were delays in the completion of procurement exercises and finalising the technical design for the deployment.

In addition, a site survey was conducted before deployment, but when the install team commenced works, they encountered several challenges preventing the fitting of required cable management systems. 

These challenges were due to limited crawl space, presence of asbestos and potential structural weaknesses in the ceiling. To ensure the installation did not impact the ambulance station, the supplier proposed the installation of access panels in each room as an alternative to the cable management system and cables in the original plan. Upon receipt of the proposal a change request was raised with both the operational management team and estates and approvals granted.

To facilitate new user onboarding, the trust also created a small primer on utilising Li-Fi dongles and how to connect in the meeting room where Li-Fi was enabled.

Li-Fi connectivity

Li-Fi was easy to install As the PoE lighting system was already being installed, it was simple to also install the required Li-Fi access points as part of this retrofit.

Connecting was intuitive Only 10% of staff needed any assistance with connecting to the Li-Fi solution after reading the primer.

Devices were able to connect to the Li-Fi solution Users in the Li-Fi enabled meeting room were able to use the Li-Fi connection on a laptop with the provided dongle. Other devices (such as mobile phones) had a more difficult time, with staff reporting difficulties connecting with a mobile phone device.

Speeds were slightly slower than available Wi-Fi Average connection speed in the meeting room using Li-Fi was 65 mbps/sec, compared to the regular Wi-Fi connection providing 67 mpbs/sec speeds. Speeds were noticeably worse when connecting from the edges of the receiver’s visual field.

Locational requirements were restrictive to users Staff felt that using Wi-Fi allowed for more freedom of movement around the space without losing connection, due to the line-of-sight requirements of Li-Fi.

Limited availability of hardware effected the deployment The trust had to downscale their initial trial scope to accommodate the difficulty of finding suppliers who are providing Li-Fi devices and sensors.

IoT Sensors and PoE lighting

Sensors now alert staff when action is required the bin level monitors send an email notification to staff when bins are approaching full, allowing clinicians to arrange timely collections and reduce the rate of unnecessary visits from wate management companies.

An example of the bin monitoring dashboard, displaying which bins have space available and which are full.

PoE Lighting provides a more centralised and easier to maintain lighting solution As PoE lights are connected with ethernet cables over copper wiring, repairs and upkeep are comparatively easier. Additionally, light levels are controlled from a centralised dashboard and can be set to turn on and off on a schedule. 

Additional functionality from radiator valves and wall switches provided teams better information by being able to review which rooms were being used remotely, the trust can ensure that heating and lighting is only used when rooms are being occupied. This will allow the trust to better plan room occupancy rotas and more efficiently provide basic amenities.
 

The application of Li-Fi technology needs a strong use case The trust advised that between requiring an external USB dongle, and having to stay still when connected, Li-Fi is not fit for general connectivity purposes. However, in situations where there is a lot of radio frequency congestion, or for a static device, Li-Fi could be a viable alternative alongside standard Wi-Fi solutions.

The trialled technologies would be more beneficial to a new build In this trial, NWAS retrofitted the PoE lighting, Li-Fi and IoT devices into their ambulance station. Doing this turned out to be more disruptive than anticipated and has increased the delay before the solution will break even financially. If an organisation is building a new site, then these deployments will be far easier to manage and can start seeing benefits immediately.

Start small and scale gradually For new PoE/IoT deployments, the trust recommends implementing a smaller installation to test and fine-tune the system, scaling up only once there is confidence in the system’s reliability and functionality. This was particularly challenging for this trial as there was no existing capability at Chester ambulance station, so a significant infrastructure alteration was required to accommodate the trialled technologies. 

Use a robust project team The trust recommends either having a dedicated lead for the project that is either based at the site or is stationed close by. They experienced several issues during the commissioning phase which affected staff ability to use certain areas of the station. During the deployment, their closest team member was over 60 minutes away, so it was challenging at times to provide a presence/support on site.

Plan to ensure deployment benefits are measurable accurately and without external influencing factors When assessing the success of a deployment, it is important to be able to properly assess the impact that the solution has made. This means both planning on how to measure them and ensuring that there is nothing influencing the potential results. 

For example, when the trust was looking to validate the cost saving benefits of their trial, they were only able to consult the station’s total electricity bills to realise them. This was not a fair test, as electric car charging points were also installed during the trial period. Ideally, the trust would have been able to measure consumption of the lighting circuits only, both before and after deployment.

NWAS explored the practical potential of IoT devices and Li-Fi solutions in a clinical setting using innovative technologies. The trust found that by using IoT devices and PoE lighting, they were able to help clinicians and estates staff with automation of many tasks that would otherwise take valuable time from providing front line care. 

Between the issues encountered during installation and mediocre usability once in place, the results from the NWAS  demonstrate that Li-Fi device sensor  is currently not mature enough to be recommended for wider use in the NHS.  
However, to meet the ever-evolving challenges of delivering modern care, the need to innovate is stronger than ever, and this trial should be commended for exploring new possibilities on how better connectivity can provide better patient outcomes and value for money. 

It is just as important to rule out technologies as it is to recommend them, and by doing this, NWAS has provided valuable information for the health sector. Li-Fi will continue to be a technology that matures, and can still find use cases in new builds, or for bespoke applications. 

NWAS is keen to build upon the IoT devices and PoE lighting already installed, and we will be sure to provide an update on their next innovative venture.