Part One | Part Two | Part Three

Chris Ruddock, Sales Director at Centreco

In part one of this series, we established that storage has crossed a commercial threshold. Now, in part two we address a tougher question: where does the real value get unlocked? 

For this we need to go beyond solar and battery technology, into energy strategy, and specifically, tariffs. 

Tariff strategy has historically been treated as simply a procurement exercise focused on securing a competitive unit rate, or in recent years, sustainability gains in the form of green tariffs. But in the context of an integrated solar and storage system, there’s a more dynamic commercial opportunity on offer. 

Having the right tariff can be the difference between a battery solution being marginal or profitable, because storage creates the opportunity to unlock value based on timing and flexibility, but only if the contractual framework allows those signals to be accessed. 

The difference between installed and optimised 

A battery sitting on site does nothing on its own; it only creates value when it is discharging at the right moment. Crucially, that moment isn’t defined by how much energy you use across a day, week or year, but by when you use it. 

As renewable generation grows, the grid experiences sharper swings between oversupply and constraint. To maintain an operational balance, pricing increasingly reflects those pressure points. Peak charges are, in effect, signals designed to encourage demand reduction when the system is under strain. 

For example, if a battery discharges at 6am when prices are already low, the commercial impact is limited. But it discharges between 4pm and 7pm, when peak pricing is in effect, the economics can look very different. 

This seems obvious, but it requires clarity on three things within the organisation that are often treated separately: 

1. Your half-hourly demand profile – Because as we’ve discussed, storage value depends on when you use energy, not just how much you use overall. 

2. Your tariff structure and peak exposure – Because batteries create financial return if they are discharging during your most expensive charging periods. 

3. Your operational constraints and flexibility – Because storage must support site operations, not disrupt them, and its performance depends on what load can realistically be shifted or controlled. 

With this alignment, storage can evolve from a static asset to a more dynamic tool. 

It’s also very important to note that a standard fixed-price contract blends peak and off-peak costs into a single day rate, with a risk premium added on top, meaning any value created by shifting demand away from those expensive 4pm to 7pm windows is captured by the supplier, not the customer. Without a tariff that reflects how and when energy is actually used, the savings from flexibility remain invisible on the bill. 

Using tariff strategy as a commercial multiplier 

If we consider that battery storage introduces control over timing, tariff structure is what determines how that control is rewarded. A battery will create financial return if it is discharging during your most expensive charging periods or charging when energy is cheapest to generate (via your own solar) or buy from the grid (perhaps overnight).

When supply exceeds demand, prices can fall sharply and at times turn negative. These negative wholesale pricing events are becoming more frequent as renewable generation increases.

With the right contract structure, this becomes an excellent commercial opportunity; charge batteries when prices are low or negative, then discharge or export when prices recover. 

You need the right contract structure, so these signals reach your system, which is why tariff optimisation can no longer be treated as an isolated procurement exercise. It needs be designed alongside solar and storage. 

The multiplier effect then becomes simple: 

• Solar reduces your cost of generation 

• Storage gives you control over when energy is used 

• Tariff strategy determines how that timing translates into revenue or cost avoidance 

The structural rise of non-wholesale costs 

One of the most important structural shifts in the UK energy system is the growing proportion of non-wholesale costs that make up energy bills. This includes network charges, policy levies and peak demand costs that represent a substantial share of total spend. 

For many organisations, the highest rates sit within a small number of high-demand half-hour periods across operational eras, which changes the optimisation target. 

This means if you want to reduce exposure to non-wholesale costs, it’s no longer sufficient to reduce overall consumption. Instead, you must reduce the cost of consumption during the most expensive periods. 

As we covered in part one of this series, battery storage enables that shift through peak avoidance, peak shaving and management and demand shaping.

Reframing energy resilience 

For most organisations, the word resilience has equated to backup generation. But today, resilience needs to include protection from: 

• Price spikes – Because sudden wholesale or peak-driven price surges can disrupt budgets and erode margin, even within a single billing period. 

• Grid congestion – Because local network constraints can limit import or export capacity at the very moments when demand or generation is highest. 

• Connection delays – Because expansion plans, electrification projects or new sites can stall if grid upgrades are required and connection timelines are stretched. 

• Export restrictions – Because generating onsite has limited value if surplus power cannot be exported or is curtailed during periods when the network can’t handle additional exports. 

• Peak-period vulnerability – Because a small number of high-demand half hours can disproportionately shape total annual energy costs. 

Within key moments of stress, storage provides greater options to navigate challenges and mitigate impacts. This in turn supports greater energy independence; not isolation or disconnection from the grid, but better visibility of how the grid is operating, your organisation’s interactions with it, and the means to reduce exposure to external shocks. 

When solar, storage and tariff strategy are integrated, resilience is not only strengthened but becomes measurable in commercial terms. This is the key difference between installing new technologies and designing a dynamic system. 

In part three, we move from design to delivery, examining what integration means in practice and how organisations can become active participants in a more dynamic energy system.