Smashing the greenhouse gas problem22 August 2023
Climate change is posing signicant problems for laundries, but with some thought and forward planning there are opportunities to mitigate the risks and the long-term effects on unit costs. Here, in a special feature, Richard Neale investigates alternative energy sources
Although it has taken many years, with many persistent doubters along the way, it is now taken as irrefutable truth that the world faces an acute climate crisis brought about by man-made emissions, particularly from the burning of fossil fuels leading to the creation of excessive carbon dioxide in the atmosphere. This is creating a ‘greenhouse’ effect, leading to progressive warming of the entire atmosphere of the Earth. The increasingly rapid melting of the polar icecaps (which is now occurring) is only one consequence. The laundering and textile rental industry is making a significant contribution to this through the direct combustion of natural gas and oil to make steam, and to heat thermal oil. In addition, it makes a more minor contribution via the purchase of electric power generated nationally by the combustion of oil, gas and alarmingly (in some regions worldwide) coal!
Every nation in the world now faces eye-watering costs to phase out fossil fuel combustion and to replace this with renewable generating capacity, based mainly on wind, solar or nuclear. In parallel with this they must upgrade significantly their national power grids to cope with over double the power demand to be met, when all transport and heating needs are electrical. The good news is that with prompt action now, and intelligent support from national governments, the laundry sector could meet the short-term financial investment required and reap long term financial benefits from the very low cost of the power flowing from green generation.
Importance of energy for a laundry
Laundry washhouses have relied historically on rapid heating using steam injection to achieve hot wash temperatures, when these were typically around 70C. This requirement has been reduced dramatically by the transition to cool washing in many regions, using advanced chemical systems to achieve low temperature emulsification and disinfection. Nevertheless, the prospect of using electric heating to raise the wash water from say 10C to 40C to meet modern requirements is not attractive, because it could extend washer-extractor processing times significantly. An electrically powered calorifier may be required. For tunnel washing, preheating the incoming flow of fresh water into the rinse zone, up to 38- 40C, should be possible, with an in-line electric heater for each tunnel.
Many small ironers already operate very well with electric heating elements, either in the bed or in the roll, so redesign of the ironer might be possible (although this could require scrapping every steamheated ironer)! Alternatively, these could be heated with steam from an electric boiler. It should be feasible to switch the heater for every thermal oil ironer over to electric heating and it should be sensible to plan for this when ordering new equipment from now on.
Tumble drying is still a very energyinefficient operation, with the thermal efficiency rarely exceeding 60%. Wasting to atmosphere 40% of the energy in expensive, electrically heated air is very unattractive, so this needs some original thought from machine designers. It is quite a challenge!
Transport will, in future, need to be either electrically driven or hydrogenpowered, and shrewd laundries will be planning for this transition now, with appropriate trials as soon as test vehicles become available.
Future energy costs
National governments are faced with very significant capital costs for new national electricity distribution grids and for new, strategically sited green generation plants. At the time of going to press, the UK government has not published cost estimates for what is required and how it is going to be funded, but the total cost could well approach £100bn. This might well be funded, ultimately, by substantial increases in the cost of power to users.
The market leaders in the UK laundering and textile rental sector have now reduced their total energy demand, from all sources, from up to 2.5kWh/kg down to around 1kWh/kg dry textiles, but there are still plenty of laundries operating at 50% above this. Getting to the target figure requires informed management and close attention to detail at every stage, involving (as a minimum) textile selection, batch weights, water levels/ flows, moisture extraction efficiency, conditioning decisions, automatic tumbler controls, ironer tuning, operator training and skilled maintenance.
At historical prices for gas of, say, 2p/ kWh and power at 14p/kWh, the average cost to the launderer would have been between 3p and 4p/kWh, based on 90% gas and 10% electrical power. So, even launderers who have learnt how to achieve 1kWh/kg textiles might be faced with an increase in unit cost from under 4p/kWh to over 20p/kWh! This would represent an increase in unit cost of over 17p/kg of dry textiles (and the suggested figures quoted might turn out to be very conservative)!
The good news is that the generation cost of green energy from wind (on which most of many countries generation would be based) should be comparable with that from fossil fuels. One recent UK wind farm contract is understood to have been set at a purchase price of 5.8p/kWh and other larger projects have mentioned prices of nearer to 4p/kWh. So once the initial capital costs for the upgrading of the grid have been met, the long-term price range could be much lower than the figures postulated earlier, but that could be thirty years away!
Local generation of power – the options available
So, what can the laundering and textile rental sector do about this? Fortunately, there are some options available. Although the UK national grid is having problems accommodating power from some of the large new wind farms now being put forward by commercial developers, the existing grid does have some capacity to take more. This capacity is in small local pockets of various capacities, distributed across the country, and many opportunities exist for small scale input in the range 1 to 10MW. This might seem tiny in comparison with the 1GW (=1000MW) wind farms now being planned, but 5MW should be sufficient to power the average laundry in future and even the largest is unlikely to require much more than 10MW. Any surplus above laundry requirements would be fed into the grid locally at a fixed price to be paid to the laundry.
This means that a small wind turbine that could be located less than say 0.5km from the laundry would provide much of the power needed. A laundry with a present peak demand of say 500kW (=0.5MW) of power might in future require 10 times this or 5MW (to replace fossil fuel used for heat generation). If the laundry were to erect a 10MW turbine then this would supply power whenever the wind was blowing (which in the UK would be for much of the time). The wiring would be arranged such that if the windspeed gave 5MW, the turbine would supply all of the laundry demand at a cost (for maintenance, loan repayments and interest and so on) of perhaps 6-8p/ kWh. If the laundry demand was below the turbine output, then current from the national grid would automatically make up the shortfall (at a probable price of over 20p/kWh). If the laundry demand was above the turbine output, then the surplus would feed into the grid and the laundry would be paid at the feed-in tariff for this. This tariff is currently set at about the same level as the fixed costs of the turbine, so it does at least provide a source of income to the laundry that roughly matches this.
Obviously, the greater the size of the turbine, the more likely it is to meet the laundry demand whenever the wind is blowing. The link into the grid provides the essential back-up when the turbine is becalmed. Solar power is less attractive to a laundry, which can require peak power all the year round, because solar generation is heavily weighted to the summer months. The wind can blow at any time around the clock, whereas daylight hours are severely limited in the winter (when many laundries are very busy).
Some laundries, unable to find a suitable site for wind or solar generation, might instead consider hydrogen power, which would enable the use of existing boilers and heaters (with some modifications), but this is currently more expensive than green generation. This might change in the future and although this seems unlikely at present, LCN will keep you updated.
Planning for green generation
The challenges of installing and running a wind turbine are not for the faint-hearted or the impatient. The first task is to estimate the power required and the size of turbine, allowing fully for the substitution of current fossil fuel used for heat generation. The next is to establish whether there is a suitable site available and the likely planning constraints involved. There are local green energy specialists in most regions who can provide invaluable assistance with all of this.
Once you know what is needed and have minimised the risks of constraints, the next big task is to establish whether the national distribution network locally can accept automatically any surplus generated. This negotiation could take a few weeks. Finally, you will need to do a check on the financial viability to ensure this is all profitable, and submit the project for planning permission. Despite the fact that every country faces a climate crisis, the outcome of any planning application is still subject to local political scrutiny and decision, and this is often unpredictable, so it is unwise to commit any major expenditure until this is obtained.
Is it worthwhile?
The contribution which green generation by a single laundry and textile rental plant can make to the national problem is more than ‘a drop in the ocean’ but is nevertheless quite small. However, the national contribution which one country’s entire laundering sector can make can be very significant, even if only a percentage of laundries get permission and make the investment. The really important deciding factor is the immediacy with which the textile care sector could deliver results. Whilst national governments agonise over the enormous costs involved in new, large-scale green generation and multiplication of grid capacity, the laundering sector could deliver significant results within the next five years!
Climate change is posing significant problems for laundries, but with some thought and forward planning there are opportunities to mitigate the risks and the long-term effects on unit costs. We hope this article has inspired some thoughts and we look forward to hearing some of your plans. Please address any queries to The Editor, LCN….