What is MSW?
What is carbon based waste?
Is MSW the same as RDF?
Are there any types of waste the W2T system can't use?
Isn't it better to recycle waste rather than burning it to produce energy?
Do you need a particular mix of waste in order for the W2T system to work effectively?
How will fuel feedstock of waste be obtained?
What is a gate fee?
How will your process affect the environment?
What is gasification, and what is gasification with plasma?
How robust is the gasifier technology?
What is vitrified slag?
Why is your process better than incineration?
What about CO2?
What about waste ash?
What is the overall Carbon Dioxide footprint profile?
What is so special about AFC Energy fuel cells?
Why do you think a combination of gasification/plasma and fuel cells will work now?
Do the AFC Energy fuel cells use platinum, and does that make them expensive, especially if demand for them increases?
What is a ROC?
What is the energy balance of the plant?
How many homes could be powered by a W2T generation plant?
Where do you identify your early mover applications?
When will your process be up and running?
Wouldn't it better for local authorities to establish the plants themselves?
What would happen to viability if ROCs were discontinued under a future government? Also, how does it affect establishment of the process in other countries?
Where will you build your plants?
Can the process be used by large industrial sites?
What is MSW?
The description, Municipal Solid Waste, covers all rubbish or refuse collected from the kerbside for disposal by local authorities. It includes food waste, plastic, paper, cardboard, garden waste, metal and glass. Many of these materials are increasingly sorted either before or after collection for recycling, but there is inevitably some part that cannot be recycled economically and is sent for disposal by landfill or incineration.[Top]
What is carbon based waste?
This includes paper and cardboard, textiles, plastics and organic material such as food and plant material.[Top]
Is MSW the same as RDF?
‘Refuse derived fuel’ is a description sometimes used to describe types of waste that can be incinerated to provide energy or generate heat.[Top]
Are there any types of waste the W2T system can't use?
Metal and glass are not suitable but they are the types of waste most likely to be sorted out from the MSW stream and recycled economically.[Top]
Isn't it better to recycle waste rather than burning it to produce energy?
This method of waste management works hand in hand with recycling. Recycling is a good solution for certain types of waste, those where there are already established collection, sorting and handling facilities and a steady market for the recovered materials. So yes, reduce, re-use and recycle as much as possible, but whatever waste is left over can now be recycled as energy in a highly efficient way.[Top]
Do you need a particular mix of waste in order for the W2T system to work effectively?
Ideally a mix made up of 35% organics, 35% paper and cardboard, 25% plastic and 5% other materials works best. If it is sorted in advance, then the mix can be checked before entering the gasification process.[Top]
How will fuel feedstock of waste be obtained?
Given the need for clean segregated carbon based inputs we intend to enter into partnerships with waste logistics companies. Full economic appraisal of feedstock gate fees against the local market conditions will also be undertaken.[Top]
What is a gate fee?
A gate fee is the amount charged by a landfill site for every tonne taken there for disposal. It has two parts: the landfill tax and the operator's disposal charge. By diverting waste from landfill Waste2Tricity will benefit from the latter charge.[Top]
How will your process affect the environment?
The Waste2Tricity process will have a positive effect on the environment in a number of ways:
- Existing landfill waste streams can be diverted in order to produce clean electricity.
- With less landfill, the future emission of undesirable greenhouse gases such as methane can be much reduced from that source.
- It is potentially a more efficient form of electricity generation in terms of reducing carbon emissions when compared to existing fossil fuel, most renewable or other waste-to-electricity models such as incineration.
- In contrast to incineration, the plasma gasification process emits fewer pollutant gases, and no fly ash or waste ash. Harmful particles, such as dioxins, are destroyed by process itself.
- A by-product of the process is inert vitrified slag, which can be used as road-building aggregates, reducing demand for gravel extraction.
- The facilities can be built on existing landfill sites, reducing the likelihood of opposition to their construction, and can utilise existing infrastructure such as roads built for waste transport.[Top]
What is gasification, and what is gasification with plasma?
Gasification is an existing technology similar to an incineration process except that it limits the amount of oxygen (air) in the burning process. This causes the waste to breakdown into its component gases - a mixture of hydrogen, carbon monoxide, carbon dioxide and a small percentage of other gases and tar. Plasma is an extremely high temperature source (at 8000+°C) and eliminates all of the tar and several of the other toxic gases plus reducing the residue to an inert vitrified slag.[Top]
How robust is the gasifier technology?
Gasifier and starved air processes are well established around the world. In the UK these have not become commonplace due to low levels of landfill gate fees but as the latter escalate due to annual increases in taxes more entrants are appearing to act as benchmark exemplars.[Top]
What is vitrified slag?
It is the metal and mineral residues that are not turned to gas during gasification, forming an inert, non-leaching, glassy material. It has potential to be used as an aggregate in road building.[Top]
Why is your process better than incineration?
In short, not only does our process eliminate the issues of air pollution and waste ash but also will produce at least twice as much electricity for the National Grid for every tonne of MSW processed.[Top]
What about CO2?
Our process efficiently converts the carbon in the waste to CO2, eliminating methane produced by land filling waste, and maximises the energy that can be recovered from disposing of MSW. The electricity generated for the National Grid actually saves coal, gas or oil being burnt in conventional power stations. This means this process will make a positive contribution to reducing the amount of CO2 generated by the UK.[Top]
What about waste ash?
Incineration can produce 25% ash for every tonne of MSW burnt and this has to be treated and buried. Because our process uses vey high temperature plasma arc the amount of waste is much smaller [potentially less than 5%] and is in the form of vitrified slag. This is so inert it can be used in construction as a substitute for aggregate.[Top]
What is the overall Carbon Dioxide footprint profile?
DEFRA have recently released their consultation document on the proposed PAS 2050 standards which will apply to carbon footprint evaluation. As a result of the substantive improvement in fuel to energy conversion efficiency in this process we are totally confident that the CO2 output per tonne of throughput will be dramatically lower than the extant conventional systems. Until the final version is running on an industrial scale, however, we feel it would be imprudent to speculate on the absolute level of reduction.[Top]
What is so special about AFC Energy fuel cells?
AFC Energy fuel cells are a revolution in the oldest, most proven hydrogen fuel cell technology, as used today by NASA.
The AFC fuel cells have three unique advantages when compared to other systems. Firstly, as low temperature units standard engineering plastics are used in construction, this and careful engineering design means low cost. Secondly, the stack has been replaced by a serviceable cartridge, allowing a five-year fit for purpose warranty. Thirdly, at 55% alkaline fuel cells have the highest conversion efficiency of any fuel cell system so their deployment will produce more electricity than any other system type.[Top]
Why do you think a combination of gasification/plasma and fuel cells will work now?
Given ROCs and the price of electricity there is for the first time an overwhelming business case to drive development of these technologies and bring them to successful operation.[Top]
Do the AFC Energy fuel cells use platinum, and does that make them expensive, especially if demand for them increases?
Platinum is currently used in AFC’s demonstrator projects, but the company is developing a non-precious metal electrode. Even with the platinum model the additional cost is marginal, as it is recovered at the end of the fuel cell’s life and either recycled or sold.[Top]
What is a ROC?
The Renewables Obligation came into force in April 2002 as part of the Utilities Act (2000). It requires power suppliers to derive from renewables a specified proportion of the electricity they supply to their customers. This started at 3% in 2003, rising gradually to 10.4% by 2010, and 15.4% by 2015 and the Obligation is guaranteed in law until 2027. Eligible renewable generators receive Renewables Obligation Certificates (ROCs) for each MWh of electricity generated. These certificates can then be sold to suppliers, in order to fulfil their obligation.[Top]
What is the energy balance of the plant?
Our calculations suggest that each plant processing 50,000 tonnes of prepared MSW per year would supply the National Grid with a nett of 48k MWh per year from the Stage 1 ICE phase & 79k MWh per year from the Stage 2 fuel cells.[Top]
How many homes could be powered by a W2T generation plant?
We estimate around 22,500 homes could be powered by a W2T plant, but of course there are many variables to take into account.[Top]
Where do you identify your early mover applications?
Early movers will be either an existing multi site waste operator that could supply a reasonably homogenised waste flow from their existing throughput or a multi sited large supermarket or restaurant chain that is already (like ASDA) or could (like McDonalds) backhaul a fairly homogenised waste stream consisting of the preferred components. We would intend to commence serious discussions upon the achieving of the first milestone.[Top]
When will your process be up and running?
The Stage 1 plant could be ready in about three years, with Stage 2 operational in about five years.[Top]
Wouldn’t it better for local authorities to establish the plants themselves?
We would be happy to develop these in conjunction with local authorities.[Top]
What would happen to viability if ROCs were discontinued under a future government? Also, how does it affect establishment of the process in other countries?
ROCs are in place to encourage the adoption of renewable schemes, but even without ROCs, the Waste2Tricity process will still be viable.[Top]
Where will you build your plants?
Existing landfill sites are an obvious place, as they are already receiving waste and the transport infrastructure exists. The plants could also be placed alongside existing incinerators, eventually taking over from them. Otherwise they can be built on other industrial or brownfield sites.[Top]
Can the process be used by large industrial sites?
As long as there is a minimum annual supply of 30,000 tonnes, plus of a homogenised waste stream available, then it is operable.[Top]