Into the belly of the Green Dragon. After a week of trying to avoid the gaze of the green dragon that dominates the southern view from the BCS Gastehaus (our accommodation for the week), we ventured into its midst.
The green dragon is an incinerator, run by a municipal company ZAST, which burns 160,000 tonnes of (perceived) unrecyclable waste per year.
From this waste it can generate up to 30MW of heat and 8.2MW of electricity, or when the heat demand is low, up to 13.7MW of electricity.
This heat is transported 2km to a district heating scheme generation/distribution centre in neighbouring Suhl. The district heating scheme, run by a municipal company SWSZ, heats most of Suhl and some of southern Zella-Mehlis. SWSZ has 300 customers, including private homes and companies. It wasn’t detailed, but these 300 customers probably include groups of private homes as one customer.
A domestic customer is charged 7c/kWh for this heat, which considering gas for a domestic customer is about 6c/kWh, means that this is very good value. Just on fuel consumption alone a boiler would have to be better than 85% efficient to match this.
The visit to the incinerator was the most difficult event of the week for me to deal with as I have actively campaigned against them in the past. I perceive them as a waste of energy, rather than energy from waste plant when one considers the embodied energy in the items being incinerated. In the waste bunker that we were shown I saw a complete mattress and a sofa (see image below) - both items that could, at least, be recycled for their material content. Once burnt, there is no possibility to recover the materials in the waste, and burning does create more toxic chemicals that require more sophisticated handling and eventually landfill.
Anyway these are well rehearsed arguments. I accept that I am being idealistic and I don’t want to sound as if I am carping after an amazingly inspiring week. I feel that I am going to need a few weeks, if not months, to digest what I have seen and learnt. I really believe that in years to come, I will look back on this week as a significant juncture in my career.
Chris Rowland - OVESCO
Live & Let Die, in the end everything is recycled. On the menu for today we had CHP district heating and heat from waste. First stop was the SWSZ CHP plant generates heat and power and was build in 1990’s. They use gas and oil depending the price of the fuel (Germany imports all of it’s fossil fuel gas and oil).
The heat is distributed in Zella-Mehlis to businesses, flats and public buildings at 7 cents/kWh. Insulated pipes supply the town through a 25KM long primary and secondary network, which is mostly underground with the exception of some areas where the ground is too hard. The gas boilers run continuously 24/7, however the two 4.5MW turbines, which are similar to jet engines do not run all of the time (see image below), because the waste to heat plant in Zella-Mehlis also provides heat and power to the town. This plant is in effect a backup to the new waste treatment plant situated at another site. Buildings were is set back onto the landscape and were not very noticeable in the town. The reduction in the towns population since unification took place, has also meant that there is a reduced demand for the heat and power and there is now a problem with the base load.
In the afternoon we visited the RABA Sudwestturingen waste treatment plant on the other side of the town, which provides the safe disposal of waste for more than 500,000 residents and the business community in the South West region of Thuringia. The plant became financially viable when targets for recycling waste came into effect in 1996 and it now provides the safe disposal of waste for more than 500,000 residents and the business community in the South West region of Thuringia. This building is very prominent in the town and is lit up at night for safety reasons. There was opposition it construction five years ago. Last year 2000 people visited the site and opposition has bee reduced by the companies efforts to engage with the community and explain the benefits of plant to the town of Zella-Mehlis. We had the opportunity to see most of the site including the crane operators viewing point where the waste is lifted into the bunker for burning, which was not unlike something out of James Bond film and there was even a chance to site in one of the drivers operation chairs (see image below). The manger went to some lengths to explain how the plant was run to stick safety rules and publishes its emissions data on their web site. I was left with an uneasy feeling having seen how the opposition to the waste heat plant in Newhaven.
Both Tom and I noticed that all the mangers at the sites we visited were very helpful and keen toVeolia waste to heat plant at Newhaven, which is in comparison architecturally more attractive than the one plant in Zella-Mehlis. I now realise where the idea for the proposed water park in Newhaven comes from assuming, but would such a scheme bring benefits to the homes and businesses in Newhaven? Is a water park really the best use of this heat? This trip has widened our understanding of large scale infrastructure projects for towns and states, but are these just required to make the transition to low carbon economies? Are we heading for a future which relies on infrastructure of this scale or can we reduce and scale down demand to decentralise the need for services?educate us and the general public about what they are doing. Perhaps Transition Town Lewes should request a visit to the 16M
SWSZ http://www.swsz.de/
ZAST RABA Sudwestturingen http://www.zast.info/raba_swth.html
Veolia Newhaven http://www.waste-management-world.com/articles/2012/07/veolia-opens-16-mw-newhaven-waste-to-energy-plant.html
Tom and Chris would like to thank Dirk, BSC and all those who made this programme, so interesting and useful.
Lee Rose - Norfolk Solar
A leisurely start today.....10am at SWSZ, the local district heating and power operator for Zella Mehlis and Suhl towns. This is my first experience of a district heat and power network, and i was impressed by the enthusiasm of the SWSZ engineer leading our tour (this enthusiasm and professionalism has been demonstrated on practically all of our site visits throughout the week; these people are clearly and rightly proud of their work). in terms of scale, the numbers are mindblowing...... eg, 1,000,000 litres of oil fuel stored on site. StadtWerke (SWSZ) supplies virtually all of the buildings within 2 kilometres with heat and electricity and has capacity to do much more (mainly because the population has contracted since reunification).
There's a tie with our afternoon visit to the local incineration plant, which provides upto 30MW of heat and 8MW of electricity to SWSZ from burning municipal waste.
The incinerator plant tour featured an insight into the whole cycle from waste truck delivery through to heat and power export, and removal of ash and dust from the site. The viewing glass into the burn chamber has a most amazing view of a huge pile of rubbish burning intensely at 1000 degrees C, and the burn chamber loading crane is enormous..... we had a chance to look straight down four storeys into the waste bunker from the crane operators room. Thanks also to the staff at BCS for laying on a celebration lunch today.Jake Rendle-Worthington - Solar Aid
An even later start today (much appreciated), which gave me the time to take a quick walk around the mainly coniferous forest surrounding Zella-Mehlis, extremely pleasant on such a sunny morning. Our first trip of the day was to the SWSZ - community heat and power plant that distributes to the whole of Zella-Mehlis and Suhl. This enormous facility supplies heat through a network of highly pressurized 30cm diameter hot water pipes to 3000 customers in the area, basically all of the 50,000 or so inhabitants of the two towns. It also exports electricity to the grid. There are several turbines resembling jet engines that each produce 4.5MW of electrical power and 8.4MW of Thermal power. These feed hot water to a massive pressurised hot water tank. Since the installation of the waste to power plant (our afternoon trip) extra heat energy has been imported to the system from here reducing the need to burn gas and oil to fulfil the network’s demand for hot water.
We were treated to a lunch at BCS which was the best meal we had had so far, possibly because Herr Gerlach the director was dining with us! We took this opportunity to thank Herr Gerlach and give feedback about the excellent access to facilities and trips that they had organised for us as well as a few comments on what could have improved the trip for us, all taken with good will. We were also presented individually with a certificate of attendance for ‘Building and sustaining low carbon economies’. At least I have proof for my family back home now!
In the afternoon we made a visit to the waste to energy plant that we could see just the other side ofthe road from our guesthouse. The director here gave us a very professional presentation on the workings of the plant, and like all the facilities we had stayed in, eaten at and visited in Germany, everything was immaculately clean and tidy. He then took us on a tour of the plant. Basically non recyclable waste from the surrounding population is brought in on trucks, scanned for radioactive material and weighed then tipped into a enormous concrete waste bunker, which is held under negative pressure to prevent unwanted fumes and smells from escaping into the locality. Here it is mixed up and then deposited into a huge furnace by a giant grab. We had the opportunity to look into the actual furnace through heavily shielded portholes and I can only describe what I saw as a burning pit of hell for refuse. The heat is then either used to generate electricity up to 40MW or heat water that is pumped to the SWSZ where it is then distributed to the town. The exhaust fumes then have to pass through a complicated multistage filtration process before being released. The content of these fumes is heavily monitored and is the one part of the whole process that may be monitored remotely as this has to comply with very tight emissions controls. The cinders left from the burn are also disposed of carefully, being handed over to another company that extracts any ferrous and non ferrous metals and then disposes of the rest in land fill. Given that waste in an inevitable part of modern life this seems like a brilliant solution and the local community although having had much antipathy to the construction of the facility now enjoys the benefits of heat and waste disposal. Considering that we have spent a week accommodated virtually in the shadow of this plant the tight environmental controls seem to be working, in fact the only time I detected a faintly funky smell was when we entered the furnace room, right in the guts of the building!
John Shaw - Burnley College
As we had not far to travel to our visits today, a later start saw the group on a tour of the local District
heat and power plant SWSZ... This supplies 30MW of heat and 13.5 MW of power to 300 customers ... Including public housing and industrial complexes. The facility burns either oil or gas...market price dependant, to supply heat and energy, with 25 KM of flow pipe and the same for return...with a pressure of up to 30bar... Impressive building services indeed!! It also utilises excess heat energy supplied from the local waste incineration plant...which we will visit this afternoon.. About 2 km away In fact... With the falling population in Suhl dropping by over 20,000 since the Wall came down in 1989... to 35,000 people ...The town has less requirement for energy and therefore the SWSZ plant mainly uses this surplus heat as its main source, supplementing this heat source with their oil and gas burning capability only in the depths of winter...when the heat load is much higher.
Once again we were surprised at the cleanliness of the site... In particular the oil loading bay was spotless ( see photos) and the lack of security to enter the site indicates the respectfulness of public property that we have seen throughout our tour...
Following an excellent lunch at BCS headquarters with Herr Gerlach, and Dirk and our drivers, we were presented with certificates of acknowledgement and we presented Herr Gerlach with a present and card to show our gratitude for our visit.
heat and power plant SWSZ... This supplies 30MW of heat and 13.5 MW of power to 300 customers ... Including public housing and industrial complexes. The facility burns either oil or gas...market price dependant, to supply heat and energy, with 25 KM of flow pipe and the same for return...with a pressure of up to 30bar... Impressive building services indeed!! It also utilises excess heat energy supplied from the local waste incineration plant...which we will visit this afternoon.. About 2 km away In fact... With the falling population in Suhl dropping by over 20,000 since the Wall came down in 1989... to 35,000 people ...The town has less requirement for energy and therefore the SWSZ plant mainly uses this surplus heat as its main source, supplementing this heat source with their oil and gas burning capability only in the depths of winter...when the heat load is much higher.
Once again we were surprised at the cleanliness of the site... In particular the oil loading bay was spotless ( see photos) and the lack of security to enter the site indicates the respectfulness of public property that we have seen throughout our tour...
Following an excellent lunch at BCS headquarters with Herr Gerlach, and Dirk and our drivers, we were presented with certificates of acknowledgement and we presented Herr Gerlach with a present and card to show our gratitude for our visit.
Our tour was insightful into the working of a large industrial plant, and very dusty and smelly and hot too ...I'm glad I don't work one of the shift patterns there. At the end of the tour we thanked the manage and return to BCS...we will complete our evaluations sheets tonight prior to leaving for the flight back to the UK tomorrow.
David Aspin - Burnley College
The morning session included a visit to the Beiichtgung SWSZ plant – district heating installation. We had the opportunity to walk around the plant which is built on a quarry site. The guide took the opportunity to show the group the area which is served by the plant and explained the link with the incinerator plant (ZAST). We had access to the turbine rooms and the boilers (heat exchangers). The extraction units all feed into separate flue which terminate in a 70 metre chimney.
The guide explained the full process of the plant.
Outside of the plant the 300mm diameter distribution pipework which feeds the various villages is externally sited above ground before going below ground some 200M from the plant. This is due to the stoney ground which the plant is constructed on.
The guide explained the due to a reduction of the population in the area the plant capacity output has been significantly reduced and is only generally increased in very cold weather when the (ZAST) plant is unable to cope with the demand.
The afternoon session included a visit to the ZAST incineration plant.
A representative from the company delivered a presentation which explained the process of incineration.
The company representative escorted the group around the plant. We had the opportunity to see delivery vehicles deposit waste in the collection areas before being sorted and incinerated. We had the opportunity to observe the incineration process and also the crane operation. The group also visited the central monitoring room which monitors the complete process throughout.
