Business Energy Costs in Winter: Why They Peak and What UK Businesses Can Do About It

Business energy costs in winter are the higher gas and electricity bills UK businesses pay between October and March. They rise because sites use more energy for heating, lighting and, increasingly, electric vehicle charging, while wholesale prices for winter delivery are higher and peak-time network charges concentrate on weekday evenings. Solar PV, battery storage and smart EV charging reduce these costs by cutting grid purchases and moving demand out of the most expensive hours.

 

This guide explains why winter is the most expensive season for business energy, then sets out how each technology helps, where its limits are, and how to combine them on a commercial site. It is written for finance directors, facilities managers and fleet and operations leads at UK commercial, industrial and public sector organisations.

 

 

 

 

Key Takeaways

 

• Business energy costs in winter rise through volume and timing: heating, lighting and EV charging demand increases while indicative winter 2026 wholesale power was around 43% above summer 2027 on 13 October 2026.
• The 16:00 to 19:00 weekday window is the most expensive time to draw grid electricity, because DUoS red band rates apply and Capacity Market charges for 2026/27 are calculated on this window from November to February.
• Battery storage is the technology best matched to winter, because it can charge overnight or from solar and discharge in the evening peak, although savings should be modelled on the DNO tariffs that will apply when it runs.
• Solar PV generates around a fifth of its summer output in winter, so its business case is annual, but every winter kWh it supplies avoids winter-priced grid electricity, CCL and network charges.
• Electric vehicles use more energy in the cold, with What Car?’s 2024 winter test showing an average 18% fall in range against summer, so fleet charging schedules matter most in winter.
• Smart charging rules already default workplace chargers away from 16:00 to 22:00, and the Workplace Charging Scheme pays up to £500 per socket until 31 March 2027.

 

 

Why are business energy bills higher in winter?

 

Winter business energy bills are higher because consumption, wholesale prices and peak-time charges all rise at the same time as on-site solar generation falls. Knowing which of these drivers affects your site most determines whether solar, battery storage, smarter EV charging or a combination will deliver the largest saving.

 

Businesses use more energy in winter

 

Space heating is the largest energy end use in UK non-domestic buildings, at around 42% of consumption, with internal lighting the largest electrical end use at around 13%. These shares come from the Government’s Building Energy Efficiency Survey (BEES), which remains the basis for services-sector end-use splits in DESNZ’s Energy Consumption in the UK 2026, published in September 2026.

 

Lighting demand moves into the most expensive part of the day in winter. In December 2025, sunset across central Great Britain fell between 15:45 and 15:51 for most of the month, with around 7 hours 22 minutes of daylight on the solstice, so lights run through the whole 16:00 to 19:00 peak.

 

Electric fleets add a newer winter load. In What Car?’s 2024 winter range test, twelve electric cars covered on average 18% less distance than in summer, even at a mild 10 to 11°C, which means more kWh per mile for businesses charging electric vans and cars.

 

Wholesale energy for winter delivery costs more

 

Wholesale electricity for delivery between October and March trades at a premium to summer delivery, because UK gas demand peaks with heating demand and gas-fired generation sets much of the power price. On 13 October 2026, Catalyst Commercial put indicative forward baseload power at around £171/MWh for Winter 2026 against around £120/MWh for Summer 2027, a winter premium of roughly 43%.

 

The National Energy System Operator (NESO) expects electricity supply to remain secure this winter, with a 5.5GW margin over expected peak demand, while noting that gas and power prices remain above winter 2025/26 levels. For businesses, the main winter risk is price rather than supply.

 

Peak-time charges concentrate on winter evenings

 

Several non-commodity charges make electricity used between 16:00 and 19:00 on weekdays more expensive, and the Capacity Market charge is measured only from November to February. This is the window where heating, lighting and fleet charging overlap, and it is the window battery storage and smart charging are designed to target.

 

On-site solar generates less

 

Solar PV produces far less electricity in winter, so businesses with solar import more grid electricity at exactly the point when it costs most. Our guide to solar panel performance in winter, estimates winter output at around a fifth of summer output.

 

The table shows that no single technology addresses every winter cost driver. Solar mainly reduces how much grid electricity a site buys, while battery storage and smart EV charging mainly change when it buys it.

 

Why does the 16:00 to 19:00 window matter so much in winter?

 

The 16:00 to 19:00 weekday window matters because Distribution Use of System (DUoS) red band rates and Capacity Market charges both fall within it, making it the most expensive time for a business to draw electricity from the grid. It is the single biggest timing factor in commercial electricity costs in the UK, and the main target for battery storage and EV charging schedules.

 

What are DUoS red band charges?

 

DUoS charges are set by the 14 regional Distribution Network Operators (DNOs) to recover the cost of the local electricity network, and half-hourly metered sites pay different unit rates in red, amber and green time bands. According to Modo Energy’s July 2026 guidance, the red band typically runs from 16:00 to 19:00 on weekdays, consuming energy in it can cost up to 10 times more than at other times, and exact timings should be checked against each DNO’s charging statement.

 

The gap between bands is changing. Drax’s January 2026 analysis of 2027/28 distribution tariffs found fixed DUoS charges rising by around 58% on average for a typical low voltage business, while amber and green rates more than tripled in the North West, so battery savings should be modelled on the tariffs that will apply when the system is running rather than on today’s rates.

 

How is the Capacity Market charge calculated?

 

For the 2026/27 delivery year, suppliers’ Capacity Market charges are calculated from customer demand between 16:00 and 19:00 on working days from November to February. Suppliers pass this cost on to business customers, so lower consumption in that window reduces a site’s share.

Triad charges no longer play a part. Since 1 April 2023, the residual element of transmission (TNUoS) charges has been a fixed daily charge per site, so winter strategies should focus on the DUoS red band and Capacity Market window instead.

 

How much of your electricity falls in the peak?

 

A site drawing 50 kW between 16:00 and 19:00 uses 150 kWh per weekday in that window, or roughly 12,000 kWh across the 80 or so working days from November to February. Half-hourly meter data from your supplier or energy management system shows your actual figure, and it is the starting point for sizing a battery or setting EV charging windows.

 

How do solar, battery storage and EV charging work together to cut winter energy costs?

 

 

Solar PV reduces the electricity a business buys, battery storage moves when it buys it, and smart EV charging controls one of the fastest-growing loads on commercial sites. Combined under one energy management system, they reduce both the volume and the timing costs that make winter business energy bills higher.

 

The three technologies are complementary. Solar earns most in summer, the battery earns most in winter, and smart EV charging stops new electric fleet demand from landing in the most expensive hours.

 

For businesses asking how to reduce business energy bills in winter specifically, the order of impact usually runs the other way round from summer. Shifting load out of the evening peak with storage and smart charging tends to matter more in winter, while solar does most of its work across the rest of the year.

 

Does solar PV reduce business energy costs in winter?

 

Solar PV reduces business energy costs in winter, but by much less than in summer, because UK winter output is around a fifth of summer output and generation stops before the 16:00 to 19:00 peak. The investment case for commercial solar rests on annual savings, with winter contributing a smaller but higher-value share.

 

What does solar contribute in winter?

 

Every kWh a solar system supplies in winter displaces grid electricity bought at a winter wholesale premium, plus the Climate Change Levy and network charges on that unit. On a clear winter day, midday generation can still cover a meaningful share of a site’s daytime base load, such as lighting, IT, refrigeration and ventilation.

 

Which type of solar suits winter demand best?

 

• Rooftop solar suits sites with large roofs and daytime demand, such as warehouses, factories and distribution centres.
• Ground-mounted solar allows panels to be set at an optimised tilt, which can improve output when the sun is low.
• Solar carports generate electricity directly above parked vehicles, making them a natural partner for workplace and fleet EV charging.

 

How does battery storage reduce winter energy bills?

 

Commercial battery storage reduces winter energy bills by charging when electricity is cheaper, overnight or from solar, and discharging between 16:00 and 19:00 to avoid DUoS red band rates and reduce the site’s share of Capacity Market charges. This is known as peak shaving or load shifting, and winter is the season when it delivers the most value.

 

How does a battery cover the evening peak?

 

1. Charge in the green band. Overnight, the battery charges from the grid when DUoS rates are lowest.
2. Top up from solar. On brighter days, surplus midday solar charges the battery instead of being exported.
3. Discharge in the red band. From 16:00 to 19:00, the battery supplies the site, so grid imports fall during the most expensive hours.
4. Hold a reserve. Some capacity can be kept back to provide backup power to critical loads.

 

How big does a battery need to be?

 

To cover a 50 kW evening load for the full three-hour red band, a battery needs to deliver at least 150 kWh of usable energy at a power rating of at least 50 kW. Nameplate capacity will usually need to be higher, because batteries are not normally discharged to zero and some energy is lost in conversion.

 

Sizing should be based on half-hourly data rather than an estimate. A battery sized to cover only the highest part of the peak can still deliver a worthwhile saving at lower cost.

 

What are the limits of battery storage?

• A battery does not reduce total consumption. It changes when energy is drawn from the grid, and round-trip losses mean slightly more electricity goes in than comes out.
• The value depends on tariff structure. Sites on fully fixed tariffs see the benefit mainly at contract renewal, while pass-through contracts show red band savings directly, and the gap between red and green rates varies by DNO region.
• Solar often pays back faster. EvoEnergy’s comparison of solar only versus solar with battery storage found that for most UK businesses, solar alone pays back faster per pound invested.

 

Battery storage makes the strongest case where a site has a significant evening peak, growing EV charging demand, a constrained grid connection, or a need for backup power. Our guide on whether to invest in solar or battery storage first covers this decision in more depth.

 

How does EV charging affect business energy costs in winter?

 

EV charging raises winter business energy costs because electric vehicles cover fewer miles per kWh in cold weather and fleet vehicles often return to charge during the 16:00 to 19:00 peak. Smart charging, load balancing and pairing chargers with solar and battery storage are how businesses can manage winter energy demand from EVs and keep it out of the most expensive hours.

 

Why do electric vehicles use more energy in winter?

 

Cold temperatures reduce battery efficiency and add cabin heating load, so electric vehicles travel fewer miles per kWh in winter. In What Car?’s 2024 winter range test, twelve electric cars covered on average 18% less distance than in the publication’s summer test, and fell between 21.0% and 37.9% short of their official range, at temperatures of just 10 to 11°C. For a fleet covering the same mileage year-round, that means more electricity bought in the months when it costs most.

 

How do smart charging rules help?

 

Under the Electric Vehicles (Smart Charge Points) Regulations 2021, new home and workplace charge points are pre-set not to charge between 08:00 and 11:00 and between 16:00 and 22:00, although users can change these settings. Public chargers and rapid chargers on motorways and A-roads are not covered.

 

The default settings already avoid the DUoS red band. Fleets often override them for operational reasons, so any change should be checked against vehicle schedules and peak-time costs rather than switched off by default.

 

How can depots and workplaces keep charging out of the peak?

 

• Schedule depot charging to start after 19:00, or after 22:00 where the default settings are kept, so vans returning at the end of the day do not charge in the red band.
• Use dynamic load balancing, which shares available power across vehicles by charge level and departure time, so more vehicles can charge without exceeding the site’s connection.
• Buffer rapid charging with battery storage, so high-power charging during the day draws from stored energy rather than the grid at peak.
• Pair workplace charging with solar carports, so daytime staff charging uses on-site generation where possible.

 

Is there funding for workplace EV charging?

 

Yes, the Office for Zero Emission Vehicles’ Workplace Charging Scheme (WCS) pays up to £500 per socket for installations completed on or after 1 April 2026, covering up to 75% of costs, across a maximum of 40 sockets. The scheme has been extended for a final year and closes at 23:59 on 31 March 2027.

 

For businesses, WCS-funded chargepoints must be used by staff or fleet vehicles, although local residents may use them outside office hours. Public authorities, charities and small accommodation businesses can allow customers, guests and visitors to use them.

 

EvoEnergy designs and installs commercial EV charging for workplaces, fleets and depots, including load management and integration with solar and battery storage.

 

How do you choose the right combination for your site?

 

 

The right combination depends on when your site uses electricity, how much roof, land or car park space it has, the capacity of its grid connection and whether it runs an electric fleet. Half-hourly consumption data is the most important input, because it shows how much demand falls in daylight hours and how much falls in the evening peak.

 

The pattern is consistent: solar suits daytime demand, battery storage suits evening peaks, and smart charging suits fleets. Most commercial sites benefit from at least two of the three, coordinated by a smart grid or energy management system.

 

What data do you need before a feasibility study?

 

1. At least 12 months of half-hourly electricity data, including the previous November to February.
2. Roof condition, available land or car park layout.
3. Grid connection capacity and any planned increases in load.
4. Current and planned fleet size, vehicle types and duty cycles.
5. Current energy contract type, end date and DNO region.

 

It also pays to remove avoidable load first. Fixing heating and lighting controls and switching off plant out of hours, identified from the same half-hourly data, is a core part of business energy efficiency and means solar, storage and chargers can be sized for the demand that genuinely needs serving.

 

Market-wide Half-Hourly Settlement (MHHS) will make this data more valuable. According to Elexon, all meters will be settled on half-hourly consumption by May 2027, which is likely to make evening consumption more visible in business energy pricing.

 

When should businesses install solar, battery storage or EV charging to be ready for winter?

 

Businesses should plan installations in spring and summer so systems are commissioned and optimised before the next winter, because grid connection approvals are often the longest lead-time item. Installing in lower-demand months also reduces disruption to operations.

 

Spring (March to May)

 

1. Review consumption and half-hourly data from the previous November to February.
2. Commission feasibility studies for solar PV, battery storage and EV charging.
3. Submit grid connection applications to your Distribution Network Operator where needed.

 

Summer (June to September)

 

1. Install solar PV while generation is high, so returns start immediately.
2. Install battery storage and chargepoints, and integrate them with an energy management system.
3. Apply for Workplace Charging Scheme funding before the 31 March 2027 deadline.

 

Autumn and winter (October to February)

 

1. Set battery discharge schedules to match the red band in your DNO area.
2. Set EV charging windows to start after 19:00, or keep the 16:00 to 22:00 default off-peak settings.
3. Monitor peak-time imports weekly and adjust schedules as fleet use and weather change.

 

Large organisations should also note that the qualification date for Energy Savings Opportunity Scheme (ESOS) Phase 4 is 31 December 2026, with a compliance deadline of 5 December 2027 (GOV.UK). ESOS audits can provide useful evidence for solar, storage and EV charging investment cases.

 

How can EvoEnergy help reduce your winter business energy costs?

 

EvoEnergy helps UK businesses reduce winter energy costs by designing, installing and maintaining integrated solar PV, battery storage and EV charging systems that cut grid purchases and peak-time charges. Founded in 2007, EvoEnergy has completed more than 10,000 projects, manages more than 3,500 assets across the UK, holds ISO 14001 accreditation and was named Contractor of the Year at the Solar & Storage Live Awards UK 2026.

 

Reducing business energy costs in winter starts with your half-hourly data. EvoEnergy’s consultancy team can identify your peak-time exposure and model the combined savings from rooftop solar, solar carports, battery storage and EV charging, with funding options including a Power Purchase Agreement that requires no upfront capital.

 

Make an enquiry to plan your solar, storage and EV charging installation before next winter.

 

Frequently Asked Questions

 

How much less electricity do commercial solar panels generate in winter?

Commercial solar panels typically generate around a fifth of their summer output in winter, according to EvoEnergy’s guide to solar performance in winter. Shorter days, a lower sun angle and more cloud cover reduce generation, and output usually stops before the 16:00 to 19:00 weekday peak.

 

Can a business battery charge overnight and power the site during the evening peak?

Yes. A commercial battery can charge overnight when DUoS green band rates apply, or from surplus solar on brighter days, and then discharge between 16:00 and 19:00 to avoid red band rates and reduce the site’s share of Capacity Market charges.

 

What size battery does a business need to cover the evening peak?

A site with a 50 kW load needs a battery that can deliver at least 150 kWh of usable energy at 50 kW or more to cover the full three-hour red band. Nameplate capacity is usually higher to allow for depth of discharge and conversion losses, so sizing should be based on half-hourly data.

 

Why do electric fleet vehicles cost more to charge in winter?

Electric vehicles travel fewer miles per kWh in cold weather because battery efficiency falls and cabin heating draws power. What Car?’s 2024 winter range test found twelve electric cars covered on average 18% less distance than in summer, so fleets buy more electricity in the months when wholesale prices are highest.

 

Do the smart charge point rules apply to workplace EV chargers?

Yes. Under the Electric Vehicles (Smart Charge Points) Regulations 2021, new home and workplace charge points are pre-set not to charge from 08:00 to 11:00 and 16:00 to 22:00, which avoids the DUoS red band. Users can change these settings, and public and rapid chargers on motorways and A-roads are not covered.

 

Can businesses still get a grant for workplace EV chargers?

Yes, until 31 March 2027. The Workplace Charging Scheme pays up to £500 per socket for installations completed on or after 1 April 2026, covering up to 75% of costs across a maximum of 40 sockets, and business chargepoints must be for staff or fleet use.