Open menu

Frequently Asked Questions

As battery energy storage systems (BESS) become more commonplace as businesses rely increasingly on renewable energy such as solar PV, and need to store this, or want to look at grid balancing and energy trading, we've listed our FAQs below. Want to know something more specific?

The two systems work in collaboration. In fact, renewable energy without storage is clean energy lost to the site. Many PV systems generate more energy than they need so storing that energy for later use can bring significant advantages to a business.

The batteries can be programmed to charge up when there is excess generation available and then used later to provide power either during peak energy use on site or at times of the day when the sun stops shining or the wind stops blowing.

Soon, with the mass adoption of electric vehicles, the current grid infrastructure will be overwhelmed.

That is where battery energy storage comes in. Our systems can:

  • Overcome power constraints
  • Decarbonise your EV charging
  • Reduce costs

You can read more about it in our guide which explains exactly how this works.

Operationally, the systems act in exactly the same way but there’s a world of difference in their carbon footprint. Systems that use brand-new batteries mean that lithium-ion has been mined specifically for their use.

Whereas second life systems are reusing existing batteries making the most out of technology and resources. Second-life systems, therefore, displace the environmental impact of battery production. In addition, when it comes to replacement batteries, replacing the second life battery pack is a lot cheaper than replacing a first life battery pack.

This is a common misconception. Although many of our customers have introduced a battery energy storage system alongside other clean energy measures, it does not have to be the case.

Battery energy systems can be charged using electricity from the grid. There are two key benefits to this: to store energy when tariffs are cheaper (to use when it’s not) or to solve a problem of peak loads on site by storing energy to support spikes in demand when capacity is an issue.

Our current E-STOR systems have a power rating of 300KW and a capacity of 360KWh. Our battery has enough charge in it to power the average household for over 5 weeks.

Add that the system is built to be modular (i.e., one control system managing several battery units) meaning you can add more storage as your business grows, giving you total flexibility over your site’s energy usage.

Any customer could use their BESS to provide grid balancing services. This is basically the storing and discharging of the grid to ensure an uninterrupted national supply. The National Grid pays customers for this service.

This can help cover some of the costs of the system. We work with aggregators who can act on behalf of a group of energy storage systems to access revenue on a larger scale.

We do this as a free service – it’s part of our offering from Connected Energy designed to ensure that a BESS can answer your challenges – whether that’s around peak shaving, carbon savings, or costs.

It is a human-created report that generates how feasibly effective a BESS would be on your site, as well as potential insights into the potential carbon savings and cost savings on your site.

We use as many insights from grid usage as possible, or as many accurate estimates as possible to make a reasonable judgment on the viability of a BESS to ensure the time and financial investment is rewarding for a client.

This is discovered by inputting data into our custom-built software, to provide a 100% tailored output in terms of carbon and/or cost savings, depending on the client’s requirements.”

We offer this before offering a formal business proposal to a client to ensure that we can give a reasonable insight into the potential output of our system for their specific needs, as well as give more insights into the BESS process and how it works.

Yes, but we request that you undertake the feasibility study on the key sites that are going to be most rewarding in terms of your goals – we will discuss this with you during the initial sales process to ensure we give you the most insightful data.

We can’t use this data if your site and/or energy usage has changed substantially.

We ask for a year’s worth of half-hourly data, and this should be relevant to the usage, for instance, the Covid pandemic changed a lot of organisation’s energy usage and potentially falsified data, so we asked customers to use data pre-Covid for more accurate long-term use.

If your data is no longer relevant due to site usage changes or building development, we’d recommend using estimates from sites with similar types/purposes, but this data would only be guidance.

Learn more about our feasibility study offering here.

We work with you to understand if you can, we have some initial modelling for fleet systems and some example sites of high use/publicly available EV charging, which we can scale from.

We can’t always create bespoke modelling as it’s very dependent on changing variables, so we can’t guarantee accuracy.

However, if it’s an EV site trying to solve a problem, we can estimate the likelihood of whether we can solve the issue, as a stress test.

The installation process is simple. To install, we require three elements: a suitable base, an electrical connection, and an internet connection.

The base needs to be a flat, level surface that is of suitable strength to take a 13.5T load. If this is not available, or if the container needs to be raised, then concrete pads may be required.

The electrical installation requires two connections into a local distribution board, a 3 phase power connection (630A breaker), and a single-phase connection for the system ancillaries. We would cover all requirements and suitable locations during the site survey.

Internet connection is required to manage the data that we monitor to drive the efficient monitoring of the system. We would discuss this at a site survey to understand any barriers to connecting to existing internet connections.

On the day of installation, we will have a team on-site to oversee the delivery. The system is delivered by crane so access will be needed.

Our systems come in a 20ft shipping container so enough space is required on site to accommodate a system of that size. We also need to leave approximately a 1.5m gap around the system for ventilation and to ensure a safe footprint for any manual maintenance requirements. The weight of the system depends on which system you choose, our 300kW/360kWh unit is approx. 13.4 tonnes. We will assess to ensure any needs for a support structure are met accordingly. The physical requirements can be discussed with any prospective clients depending on your site requirements.

Electrical Requirements – Power Side

  • Voltage (V): 400VAC (3P)
  • Current (A): 520A (630A Isolator)
  • Power (kW): 360kW
  • Frequency: 50Hz

Electrical Requirements – Ancillaries Side

  • Voltage (V): 230VAC (1P+N)
  • Current (A): 63A (63A MCCB)
  • Frequency: 50Hz

The system needs to be transported to the site via HGV and crane and requires a flat level surface for a safe installation. We will also need access on the day from the entrance point to the area where it will be installed.

The location for the system and access for the crane and lorry needs to be clear of obstructions, parked vehicles and pedestrians kept at a safe distance.  The ground should be prepared, and civils construction completed.

On the day of delivery, it is best to have a customer representative on site.

We find most of our customers are so excited to see the system being delivered that we often get a welcoming party with phones and cameras at the ready!

This is dependent on a range of factors. As a general guideline, we can usually deliver in around 6 – 8 weeks however several things need to happen before we can commission a system.

The key component that can cause delays is liaison with the DNO (Distribution Network Operator). Any site is required to comply with G99 regulations – this is to ensure that if the grid goes down the generator doesn’t try to feed into the network connector, as this is a safety requirement. This assessment and approval process can take some time – depending on the DNO – and is out of both our and your control – so we advise arranging this as early as possible to minimise delays to the installation date. We will ensure the scope for this is agreed between all parties – any necessary contractors, as well as the customer and the DNO.

Absolutely. During our discussions, we will factor in any on-site or external partners you may have, and can work with these to install the system, or we can offer a full package solution including electrical installation.

Our systems are a treasure trove of data. Each system provides over 2.5 million data points each day, giving you a comprehensive idea of the system’s performance. We have a dedicated in-house data team who specialises in understanding and optimising our systems constantly.

The team works with you in mind, meaning they can link up with your point of contact, be that Energy Manager, Sustainability Manager, or Facilities Manager and work with them to develop your understanding of the system, or to change its variables, to help it perform the way you need it too.

We estimate each individual battery will last seven years. The good thing about our systems is that they are built using a rack system, so if we identify any performance issues, we can easily swap and replace them for another.

In addition, our proprietary battery management system gives us data on the battery’s health throughout the day, meaning you are always aware of how your system is performing.

We offer a full monitoring and maintenance package and will ensure your system is running as it should without the need for your team to have any specialist knowledge. Following the installation, the system is handed over to the customer however our technical team continue to monitor the system in the background. Our maintenance package also includes one on-site visit per year to check everything is running as it should.

We also provide a five-year warranty which covers any electrical and mechanical issues, replacement parts and any degradation and replacement of batteries.

We work closely with automotive companies who rigorously test their battery packs to prove their quality before they are passed to us for our systems.

We also only work with manufacturers who will share their data and we use this to not only perform our own checks but to continuously monitor their state of health throughout their lives.

At Connected Energy, we have placed significant investment into our control systems which understand the individual make-up of each individual battery. If the system recognises any degradation, the system will send us a notification for us to review.

Learn more about how we work with OEMs here.

One of the additional benefits of using second life batteries in our systems is that we are able to capitalise on the safety systems that automotive manufacturers have heavily invested in. All battery packs are rigorously tested by the manufacturers.

We have also created the gold standard for managing our systems. Our systems have passed intensive energy sector compliance tests and are continuously monitored by our software which can immediately pick up on any small anomaly.

To give our customers peace of mind, our systems also include an integrated fire prevention system that will shut down in the unlikely event of a fire.

We have in-built safety monitoring and controls, as well as separate door access to the system away from the batteries. The system will perform automatic shutdown procedures if safety parameters are breached for any reason, and it has its own audible alarm. In addition, our controls team monitors the system remotely and they are alerted to any issues or unauthorised entry to the system. We can also link to external beacons, your security, or fire panel if required.


We have two emergency stop buttons fitted as standard, one inside the power electronics area, and one external button near the main incoming supply.


We use AI in our system which initiates an early warning system if any anomaly is flagged. The BESS also comes with smoke alarms. We have had no incidents throughout the lifespan of any of our BESS systems. Safety and security are our top priorities with every installation, and we provide more details on this to any prospective clients.

Connect with us

Get in touch with our team to discuss whether battery energy storage can work for your business.