The recent headlines covering the volatile and rapid increase of natural gas prices will have escaped the notice of very few consumers in the UK and across Europe. As some industry leaders have put it, if a pint of beer were subject to the same price increases as natural gas, a pint would now cost £25. Governments, including the UK, are making efforts to protect people, however the reality of how this will affect individual households in the longer term is now becoming clear.
For businesses, institutions and organisations that have no or limited protections, many are already experiencing the full impact of the substantive shifts in the gas markets.
With this in mind, the Anthesis Energy team has pulled together five simple questions that organisations should be asking to allow them to identify how to reduce gas consumption and costs. Although the interventions are focused on commercial users, many are also relevant to individuals looking to reduce consumption in their home.
1. Where is energy being consumed?
‘If it cannot be measured it cannot be managed’ is an old engineering maxim.
It has never been more important to understand your billing, metering and sub-metering arrangements and check them against real or anticipated consumption for your usage. If results appear unusual, you should be asking why and what this means.
Comparing against UK benchmarks can be another helpful way to see how you measure up to the average. Businesses can check their performance against UK benchmarks using free CIBSE tools available here. For home users, Ofgem sets a high, middle, and low consumption value based on usage statistics every year and the BBC has a helpful summary of this here.
If you have half-hourly metering, or as a homeowner have been upgraded to a SMART meter, you may be able to access detailed usage information for a more comprehensive analysis to identify cost-saving opportunities. Alternatively, a cheap and simple energy monitor can help visualise energy use and identify any areas of consumption occurring outside expectation. For example, reviewing the consumption overnight and at the weekends can lead to uncovering energy waste which can be easily fixed.
2. Do you have control?
One of the most common issues we see is a lack of proper heating control, which means systems are not accurately varying their output according to demand.
This is often more of a problem with hydraulic systems, such as Thermostatic Radiator Valves (TRV), compared with electronic systems. TRVs are often mistakenly used to control the temperature of the radiator or treated like a volume control on a stereo, with users turning it higher to attempt to heat the room faster. A TRV should be used to control the temperature of the room the radiator is in. Often either set to fully open or fully closed, they should be set somewhere between 3 or 4. Valves in the same room should be set the same and preferably there should be none in the room with a system thermostat to avoid the two systems fighting each other.
3. Are you in balance?
Another common failure is having hydraulic systems that are out of balance.
This often occurs on radiators where lockshield valves (the one that is not the TRV) have been tampered with. For example, closed to allow radiator removal (e.g. for room decoration) or fully opened by the people accidentally when radiators are replaced or turned back ‘on’. The purpose of a lockshield valve on most radiators is to reduce flow through the radiator. The resistance from this valve forces the majority of water away from just one radiator to the other radiators in the circuit. Set up correctly, the system is in ‘balance’ with all radiators receiving a small portion of the full system flow, the maximum heated surface area across the system, and therefore maximum heat exchange and boiler output. If one valve is opened too far, or fully, this causes a hydraulic ‘short circuit’ like that in an electrical system. In the worst cases, the entire system flow passes through just one radiator (the one with a fully open valve), causing the others to cool or go cold. Heat output is then restricted to the capacity of one radiator, so it can drop dramatically, and system water temperatures rise usually to the detriment of efficiency.
Rebalancing the system is required to eliminate these issues and may be as simple as intervention by facilities management mechanical technicians or a plumber.
4. How low can you go?
Inevitably people will be reaching for the thermostat to turn down heating systems, heat indoors to a lower temperature and reduce fuel usage. However, the benefits of this can only be fully realised if you have control and are in balance (see questions 2 and 3). As a rule of thumb, each 1 °C drop in internal temperature set point reduces fuel consumption by 10%. Engineering guidance will provide the lowest recommended temperature for different types of inside space, e.g. 19°C internal temperature in offices. In Germany, reduced indoor temperatures in public buildings have already been enacted by law as a national fuel-saving measure. Heating for only short periods (e.g. less than 2 hours in the morning and the evening) may not be energy efficient depending on building type and use, however heating to a reduced temperature when a facility is unoccupied (temperature setback out of hours) can reduce consumption.
Care is required for vulnerable users and, in general, unoccupied spaces even out of hours should not be set below 10-15°C to avoid excessive mould growth. Mould growth occurs when building fabric and contents fall below the dew point (about 12°C depending on use context) and water condenses out of the air onto surfaces or in fabrics, which can become a substantial health risk. For the same reason, ventilation openings should not be blocked as a draught exclusion measure as this will raise internal moisture levels often triggering damp problems. Usually, a ‘thermal comfort’ policy, describing internal set points and durations is helpful to explain expectations to users.
5. How low can you really go?
Where a condensing boiler is fitted, it is often possible to achieve the desired internal temperature of 20°C, while reducing the temperature of the water flowing around the heating system (the flow temperature). It is common for UK heating systems to have an element of oversizing (e.g. 10-20%) as a design margin. This may allow the reduction of system temperatures while still achieving the desired internal temperature either all the time or in warmer weather periods. This is beneficial as it increases boiler efficiency. Only when flow temperatures are reduced below 55°C is a boiler ‘fully condensing’ and accessing a further 10-15% of heat from gas fuel. If this can be achieved whilst maintaining the internal setpoint lower gas consumption may be accessed.
To adjust the flow temperature of your heating system you can change the temperature of the boiler. It is particularly important to do this in autumn and spring when you only need a little heat to achieve the internal temperature. Reduce the flow rate to 55°C and then as the season changes, if you need to, gradually increase it. Your building, and how much heat it retains or loses, will heavily influence the flow temperature you require.
Care is required when reducing the flow temperate for circuits serving hot water systems as compliance with Legionnaires regulation must also be achieved. However, this may be possible via changes in hot water equipment or the Legionnaires risk management regime.
The above optimisations are all potentially accessible without replacing emitters or boiler systems. Although they will not eliminate the need for gas in the short term, they may access savings of 20-35% in operations providing part of the solution in meeting the challenge facing all organisations and consumers this winter.
An interesting side effect of changes in gas prices is now many low carbon systems are the cheaper energy option. Anthesis is also now working with multiple organisations on more comprehensive interventions to ensure long-term price stability for both electrical and thermal energy is decoupled from fossil fuel pricing. This has the potential to align both financial and net-zero goals in the medium term, especially where government intervention implies short-term relief in return for higher energy prices than historic trends for the foreseeable future.
The questions above will help organisations to identify some of the quick wins to reducing gas usage. To ensure long-term resilience against energy price rises, organisations will need to find alternative low-carbon heat sources with lower exposure to fossil commodity markets. Fortunately, a lot of the steps identified above also start to open opportunities to utilise alternative low-carbon heating technologies, e.g. heat pumps. When combined with on-site renewable energy supply or alternative waste heat sources (e.g. Energy from waste), links to the fossil commodity markets may be weakened or eliminated, reducing the cost risk for organisations in the future.
