Smart Energy


With the introduction of monitoring, lighting, heat-control innovations and smart meters, we’re rolling out a range of solutions to reduce our carbon footprint and help preserve our historic places for future generations.

Climate change is having dramatic impacts around the planet. Even seemingly sturdy English Heritage sites such as Hurst Castle in Hampshire are threatened by sea-level rises and coastal erosion. Less obvious, though, are the effects inside our historic properties – effects we’re addressing with immediate remedies and wider efforts to reduce our carbon footprint. 

‘Historic properties are, in a way, uniquely sensitive to climate change, because most don’t provide the level of protection as modern buildings,’ explains senior conservation scientist Dave Thickett. ‘Whatever happens outside comes inside, to a greater extent.’ That doesn’t just mean leaky roofs and draughty windows – changes in temperature and relative humidity ranges have insidious effects on furnishings and collections.

‘We’re already seeing a significant increase in mould growth that affects all organic materials,’ he adds. ‘Very hot summers can cause damage to Limoges enamels in collections at sites such as Ranger’s House in London, so we’re having to improve chilling systems too.’

Controlling internal environments can be energy intensive – and energy efficiency is a core element of our sustainability strategy. By switching to smart meters, we’re already taking steps to monitor and reduce energy use across the estate – and this will help to save money too. Knowing exactly how much we use, when and where is crucial in planning specific solutions tailored to individual properties.

‘We recently moved to a fully renewable energy package, but we need to continue to reduce our energy usage,’ says estates director Rob Woodside. ‘We know that 60% of our energy use relates to just 10 of our sites. If we can reduce consumption in those, we’ll make a difference across the whole charity.’

Wrest Park in Bedfordshire is a good example: with the third-biggest energy footprint of our properties, largely because it’s such a large, old structure, we’ve identified several options for improving energy efficiency.

By switching to smart meters, we’re already taking steps to monitor and reduce energy use across the estate – and this will help to save money too

‘We’re currently installing pipe cladding in our plant rooms, applying mineral-fibre insulation sections to exposed steel pipework and cast-iron valves, and protecting them with aluminium sheeting,’ explains Rob Perkins, facilities manager at Wrest Park. ‘This will reduce energy loss and save us around £1,500 per year.’

Such changes in old structures must be planned carefully. For example, LEDs are far more efficient than the old-style incandescent bulbs – but not all are universally suitable. ‘Each LED gives out light at different colour temperatures,’ explains Dave. ‘A subset of them emit more light in the blue region, which can damage some pigments. So we test LEDs to make sure we install those that won’t cause damage.’

‘When considering insulation in loft spaces at Wrest Park, we can’t just put in rock wool,’ adds Rob Perkins. ‘It has to be lamb’s wool or another specialist insulation, because lath-and-plaster ceilings need to breathe. It’s an old fashioned solution to a modern problem.’

Conversely, we’re finding new solutions to old problems, such as how best to heat a historic house. ‘Over recent years we’ve been more accurately measuring how much energy we use to achieve the environments we need, with separate metering to assess how different types of systems perform,’ says Dave. ‘Now we’re putting that into practice, changing heating and control systems.’

A key modern concept is conservation heating. ‘Instead of setting a thermostat to control temperatures, in many properties we now control relative humidity, using a hygrostat to turn radiators on or off,’ explains Dave. ‘That uses about one-third of the energy of heating for comfort – and it’s better for the collection, too.’ 

Around 80% of our properties with collections now employ conservation heating systems, including energy-heavy sites such as Apsley House in London, where the top floor has humidistatic controls, temperatures elsewhere have been reduced, and more-efficient boilers installed. 

We’ve already made over 40% energy savings at Apsley House, and expect efficiency to rise even more through measures such as making buildings more airtight – a process that requires careful assessment. ‘We’ve undertaken trials on sealing windows at Apsley House, which has advantages beyond heat retention – it helps keep out London pollution,’ explains Dave. ‘But we have to be aware that most of these old buildings were designed to have ventilation; if you seal them too much, you can exacerbate issues like mould growth.’

Where appropriate, we’re generating renewable energy on site. ‘We work with very, very sensitive buildings, so we can’t just slap solar panels all over them, but there are places where it’s viable,’ explains Rob Woodside. ‘At Wrest Park, for example, we’ve installed solar panels on the café – it’s not a historic building, and there’s no visual impact on the gardens or house – and perhaps the collection stores, to produce energy for the visitor reception and interpretation area.’

We’re also installing sensors at our 10 most energy-intensive properties. ‘These collect accurate readings from different areas – in the visitor reception, in catering and so on,’ explains Rob Woodside. ‘It helps inform decisions: do we need to turn on ovens so early in the morning, for example, and how much can we save by turning down the temperature by a degree? Understanding that data is really important to help us interpret what’s happening in our properties.

‘A major motivation is saving money,’ he adds. ‘We’re aiming to reduce our energy costs by 30% over the next five years – we’d rather spend our money looking after our properties That’s just as important as reducing our carbon footprint and generally becoming more sustainable.’

Taking small steps such as installing a smart meter can help all of us understand where and how to save energy – and money. And the impacts of that could be local as well as global – helping to preserve the historic sites we love for future generations to enjoy.


As part of our commitment to working towards a more sustainable future, we’ve partnered with Smart Energy GB, the campaign for a smarter Britain, to share the benefits of installing a smart meter. 

86% of people with a smart meter have said that they have changed how they do things around the house to use less energy. They can also be used to keep track of your spending, check your tariffs, and thereby save money on your bills.

Find Out More

Planning for a More Sustainable Future

Climate change is already having a very tangible impact on the 400 properties in our care. That’s why we need to act now to become a more resilient and sustainable charity, so we can protect these historic places for future generations to enjoy. 

Watch our video to find out how we’re reducing energy consumption at Wrest Park, and using tools such as smart meters, as well as how we’re harnessing the power of green technology.

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