Coal power is dirty – but abandoned mines could help create a clean energy future

Pushing on into a bright future: the Old Meadows Coal Mine, Bacup, Lancashire, 1936. Image: Hulton Archive/Getty.

Energy from coal is now being linked to global warming and pollution on a global level. In fact, it has been estimated that coal contributes to 25 per cent of green house gases.

Coal use has caused severe negative environmental impacts, from its mining and processing, to its transportation and combustion, leading to high levels of pollution. In October 2017, a United Nations weather agency report indicated that levels of carbon dioxide surged at “record-breaking speed” compared to 2016.

Around the world, coal mining contributed historically to the industrial revolution and played an important part in the development of modern society. But many mines have since been closed in the UK and Europe. In the UK, this led to hard financial times and unemployment in many communities, including the miners’ strikes of the 1970s and 1980s, an impact recorded in the 1996 movie Brassed Off.

But what happens inside the coalmines after their closure? Surprisingly, most disused coalmines start producing methane – known as Coal Mine Methane (CMM) – which can be a clean source of energy. It can be used to generate electricity via gas engines or, with some technical processing, be fed into the gas grid. Over time, however, the mines will begin to fill with water and the methane will almost entirely disappear.

Water, water everywhere

But this will create yet another opportunity. The UK’s historic coal mines have an approximate residual void space of a billion cubic metres. When flooded, that’s the equivalent of 400,000 Olympic swimming pools of water at a stable temperature. This vast volume of water can be used for efficient heating and cooling applications and reduce carbon emissions.

But how? A recent publication by the team at Nottingham Trent University explains. The water in the coalmines is generally at a stable temperature – normally between 12C and 20C depending on the location – which makes it perfect for warming, or cooling, buildings or industrial processes.

We developed and tested a new technology for several years using two systems, one at Markham Vale and one at the National Coal Mining Museum for England, and found it can use this water to provide green, sustainable energy to homes and businesses in the UK.


Opportunities and challenges

The technology, which is based on using water source heat pumps, is simple and straightforward and works along similar lines to a refrigerator or air-conditioning system. It produces no noise or local air pollution and is also three or four times more efficient than a standard electric heater or gas boiler.

To understand how heat pumps in general work, consider the refrigerator in your kitchen. This extracts the heat from the food and drinks inside it, and diverts it into the surrounding environment via a condenser (which is simply a radiator) on the fridge’s exterior. Our technology employs a similar system. In this case, we extract the heat from the coalmine water and use it to warm buildings.

In the UK, coal mining technology programmes already pump nearly 112m megalitres of water for environmental reasons, such as avoiding the pollution of drinking water, springs and rivers. The new technology could use this water, which is being pumped anyway, potentially generating 63 megawatts of heat per year.

But the technology has its own challenges, specifically a lack of investment and “champion” organisations to lead the process. In part, this is because it remains a little-known or understood technology by many investors.

There is also a lack of a clear model to follow in the UK when implementing new technologies such as this, not just commercially, but contractually and legally as well. Most housing developers in the UK and Europe, for example, prefer to rely on well-established technologies such as gas boilers or electric heaters, even in areas where coalmines are available. If such new, green technologies are to succeed, comprehensive strategies are needed to get developers – and the general public – on board.

Hot topic

On the positive side, the technology can be integrated with other heating technologies, and in many cases existing building infrastructure can be used to implement it. The technology can also reduce carbon emissions and energy use and support compliance with the EU Energy Efficiency Directive and UK ESOS regulations.

We also have excellent, large-scale case studies, showing how effective it can be. In Asturias, north-west Spain, for example, a hospital and a university building are already being heated using coalmine water.

The ConversationOur research shows this technology could give the world’s disused coal mines a new, green, lease of life. What a fitting legacy for the industry that would be.

Amin Al-Habaibeh, Professor of Intelligent Engineering Systems, Nottingham Trent University.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

Here’s how Henry Ford and IKEA could provide the key to solving the housing crisis

A flatpack house designed by architectural firm Rogers Stirk Harbour and Partners, on display at the Royal Academy, London, in 2013. Image: Getty.

For many people, the housing market is not a welcoming place. The rungs of the property ladder seem to get further and further out of reach. There are loud calls to build hundreds of thousands of new homes (and equally loud demands that they’re not built in anyone’s back yard).

If there was ever a time to introduce mass-produced affordable housing, surely that time is now.

The benefits of mass production have been well known since Henry Ford’s car factories made the Model T back in 1908. It was only made in one colour, black, for economic reasons. Not because it was the cheapest colour of paint, but because it was the colour that dried the quickest.

This allowed the production line to operate at faster, more cost effective, speeds. And ultimately, it meant the product could be sold at a more attractive cost to the customer.

This approach, where processes are tested to achieve increasingly efficient production costs, is yet to filter properly into the construction of houses. This makes sense in a way, as not everybody wants exactly the same type of house.

Historically, affordable mass-produced housing removed a large amount of customisations, to ensure final costs were controlled. But there is another way. Builders and architects have the ability to create housing that allows a level of flexibility and customisation, yet also achieves the goal of affordability.


Back in 2006, the “BoKlok” approach to affordable housing was launched to great acclaim in the UK. Literally translated from Swedish, the term means “live smart”. Originally created from a collaboration between flat-pack favourite IKEA and Swedish construction giant Skanska, the BoKlok housing approach was to allow for selected customisation to maximise individuality and choice for the customers. But at the same time, it ensured that larger house building components were duplicated or mass-produced, to bring down the overall costs.

Standard elements – wall panels, doors, windows – were made in large numbers to bring the elemental costs down. This approach ensured the costs were controlled from the initial sketch ideas through to the final design choices offered to the customers. The kitchens and bathrooms were designed to be flexible in terms of adding additional units. Draw and cupboard fronts interchangeable. Small options that provided flexibility, but did not impact on overall affordability.

It’s a simple approach that has worked very well. More than 10,000 BoKlok houses have now been built, mainly in Norway, Sweden and Denmark, with a small number in the UK.

But it is only part of the architectural equation. The affordable housing market is vital, but the cost of making these homes more adaptable is rarely considered.

Flexibility is key. The needs of a house’s inhabitants change. Families can grow (and shrink) and require more room, so the costs of moving house reappear. One clever response to this, in BoKlok homes, has been to allow “built in” flexibility.

Loft living

This flexibility could include a loft space that already has flooring and a built in cupboard on a lower floor which can be simply dismantled and replaced with a “flat-pack style” staircase that can be purchased and installed with minimal disruption to the existing fabric.

Weeks of builders removing walls, plastering and upheaval are replaced by a trip to the IKEA store to purchase the staircase and the booking of a subcontractor to fit it. The original design accounted for this “future option” and is built into the core of the house.

The best approach to new affordable housing should consider combinations of factors that look at design, materials and processes that have yet to be widely used in the affordable housing market.

And the construction sector needs to look over its shoulder at other market places – especially the one that Henry Ford dominated over a century ago. Today’s car manufacturers offer customised options in everything from colour to wheel size, interior gadgets to different kinds of headlamp. These options have all been accounted for in the construction and costing of each model.

The ConversationThey share a similar design “platform”, and by doing so, considerably reduce the overall cost of the base model. The benefit is quicker production with the added benefit of a cost model that allows for customisation to be included. It is a method the construction sector should adopt to produce housing where quality and affordability live happily together.

David Morton, Associate Professor in Architecture and Built Environment, Northumbria University, Newcastle.

This article was originally published on The Conversation. Read the original article.