SiteGrid X45 Hybrid Battery Generator System

Hybrid Energy Management System upgrade. The additional features of our HEMS upgrade are: 

• Load shedding
• Improved energy storage
• Improved battery management
• Sophisticated quiet time settings
• Intelligent renewable energy management
• Detailed monitoring and data collection including:

• kWh generated/used
• fuel consumption per kWh
• emissions savings

• Multiple outlets on the hybrid unit which can be used and independently controlled.
• Time clock
• Light / rain / temperature sensors can be used to control power to certain sockets on the hybrid unit.
• Shedding of non critical loads to keep total consumption low.
• Intelligent generator starting via multiple start/stop parameters - capable of passing 36kW before the generator is triggered to start

• Sophisticated quiet time settings where for example, we can ensure that batteries are fully charged before entering quiet hours by starting the generator during the day if required to ensure that the quiet hours deliver silent power throughout the night successfully.

The HEMS we offer allows not only the delivery of power to the site to be optimised, but also the control of the power consumption on site also.

Below are some scenarios with the benefits explained.

Perimeter Lighting

Often perimeter lighting around the site is left on 24/7 when in reality it is only required during the hours of darkness. If we allow for 500W of LED flood lights on a site, but they remain on during the daytime from 6am till 8pm, that equates to 7kWh of consumption that in essence was not required. Our HEMS option contains a light sensor which can be used to control one of the outlets. When the sunlight reaches a certain level, the socket turns off which would mean the flood lights turn off. Then as the sun sets in the evening, the power to the socket comes back on which would turn the lights on automatically.  This can save approx.  60% of energy used for that circuit and approx. 1 hour of generator run time per week based on a 45 kVA generator.

Drying Room(s)

Drying rooms on site count as a considerable load – typically pulling approx. 4kW. Frequently they will turn on at the end of the shift and run until the morning when someone will arrive on site the next day and turn the driers off. This may be from 6pm through to 6am the next day – a total of 12 hours giving a power consumption of 48kWh. This is larger than the battery bank capacity so we know that the generator will start up in the early hours of the morning to recharge the low batteries. 

However, we can be certain that the clothes in the drying room will be dry within 3-4 hours, so our HEMS option would allow control of the socket to the drying room so that the power can be turned off at say 10pm and then turned back on the next day. This reduces the overnight consumption from the drying room down from 48kWh to 16kWh. This contributes considerably to help alleviate the overnight power consumption which in turn means the site can get through the whole night period without starting the generator. This would save approx. 60% on that circuit and around 6 hours of generator run time per week based on a 45kVa generator.

Load Shedding

Non critical loads can be shed if the system is running out of stored power or the loads were such that the generator would need to start to support the loads.  This is difficult to quantify a saving as the loads are unknown at this stage but this ability will reduce unnecessary energy usage, especially during night hours when there is a tendency to leave cabin lights and heating on, if these were considered non critical during the night they would be turned off if required automatically.

Ensuring Batteries Are Fully Charged Before Quiet Hours

The HEMS system allows the client to control their loads during the quiet hours so they can be assured that the 45kWh battery bank can get through the night without needing to start the generator by various socket control systems as mentioned above. However, looking at a basic hybrid unit, we could take the scenario that the batteries are at 70% SOC as we enter the quiet hours. At this point the generator is off and the overnight loads will draw power through the quiet hours. However, as the batteries entered the quiet hours at 70%, they may only get to 2am before they reach 20% at which point the generator will come on to charge the batteries based on the low state of charge start condition. This is fine and is what is expected of the system. However, for certain sites, there may be restrictions where generators are not allowed to run during the night – so this would not be a suitable solution. Our HEMS monitors the state of charge of the batteries and controls the generator during the day to ensure that come the beginning of the quiet hours, the batteries will be at 100%. Combining this, with the full control of the overnight loads, allows the client to calculate and ensure that the generator will not need to run during the quiet hours and the site’s overnight consumption can be delivered silently from the batteries without needing to start the generator until the next morning. Not only does this allow the local authority’s silent power regulations to be adhered to, it also contributes to loading the generator highly the next morning which increases efficiency in both fuel costs and carbon emissions when it is running.