Hever Castle is committed to becoming more environmentally friendly and efficient and is continuing the process of replacing old equipment with more energy efficient solutions.

We have now completed the replacement of our old oil-fired and LPG boilers with a new 650KW woodchip boiler. This was a massive project and cost over £500,000, which sounds like a lot of money, but when you compare it against our annual energy bills of £100,000, it starts to make more sense. With oil and gas expected to get ever more expensive, using woodchip, which is sourced from local woodland and sawmills, it is going to be not only considerably cheaper, but also much more environmentally friendly and has the added benefit of supporting local businesses – tree felling operations, haulage and chipping. This new boiler heats not just the Castle and Astor Wing, but also the Moat Restaurant, the Hever Shop and fourteen residential properties.

The high cost associated with the project is attributed to the boiler (£150,000), a new shed to house the boiler, two 20,000lt buffer tanks (these store hot water which is then circulated round the site), the large network of super insulated pipework (the boiler house is 300m away from the Castle) and the interface units. Essentially the water heated from the boiler is stored in the buffer tanks and then large pumps circulate it around the site. The individual properties continue to have their own hot water and heating systems, but instead of an oil or gas boiler, biomass hot water is used to heat the water in the pipeworks of the receiving properties via an interface unit. It is possible and indeed cheaper to have a direct system, but the danger of that is that if any one property has a leak and no-one notices it, the whole system can drain down with potentially disastrous consequences, particularly for flooding (40,000 litres can cause a lot of damage). The properties are also all individually metered so that we can monitor heat usage throughout the site.

You will see on this page various photographs showing the installation work and the finished product. This project would not have been possible without £140,000 of grant from the Department of Energy and Climate Change and a £100,000 Carbon Trust loan. We congratulate the Government on making these grants available, as they should ensure this relatively fledgling technology in Britain becomes more commonplace, which is clearly good for the environment and for local economies, particularly in the south-east, which surprisingly is one of the most wooded parts of the country. Our own woodlands will start to be managed in a slightly different way to help ensure a cheaper supply of timber for the Estate in the future. It is worth noting that chestnut coppice, a traditional crop to the south-east, which is recognised for its wildlife benefit, is one of the best types of woodland to feed woodchip boilers.

We are intending to further pursue the possibility of hydro power from Hever Lake. Further analysis on this will take place later in the year.

As a consequence of the new heating system at the Castle, we have been replacing all the insulation on the pipework in the cellars, which is no light job. Much of the old insulation was asbestos and this was removed last year. So far we have reinsulated 1,100 metres of heating and hot water pipes and have a further 500 metres to complete. The next phase on the heating front is to zone the Castle complex and then start a system of replacing all the thermostatic valves, many of which no longer work.

The big project we are currently undertaking is the renovation of our sewage system. The sewage system at Hever Castle is approximately 100 years old and it was with some sadness that we replaced the 100 year old injectors that injected the sewage using compressed air over a mile away to old fashioned settling ponds. The injectors have been replaced with macerating pumps, which are more energy efficient and will be easier to replace in the future. The Castle is using a firm of consultants called Living Water, who have particular expertise in coming up with ecologically sound solutions to sewage and indeed polluted water. With the co-operation of the Environment Agency, we will be renovating the old lagoons and through the use of different grades of aggregate and specialist planting, the old lagoons will be transformed into a series of wetland habitats and lagoons, that will not only purify the sewage converting it to water, but it will also support a healthy and diverse range of wildlife. The main reason to go for an ecological solution for Hever is that we are too far away to connect to a mains sewage system (the cost of connection would come to many millions of pounds), and traditional mechanical sewage systems would not easily cope with the large fluctuations we have with visitors here. Traditional mechanical systems would also require a considerable amount of servicing throughout the year, not to mention power, which would be expensive.

Updated 19.05.2009