As much of the UK is consumed by #Snowmegeddon, our focus is on staying warm and perhaps the expected rise in our energy bills this month.
What consumes the most energy? Is it heating or artificial cold?
The answer is determined by these five points:
- The number of Heating degree days vs Cooling degree days
- The Building Energy Management System (BMS) strategy
- The source of the energy
- Human behaviour and modern expectations
- The efficiency of the heating and cooling equipment
The number of Heating degree days vs Cooling degree days
The energy demand for heating and cooling is known as Heating Degree Days (HDDs) and Cooling Degree Days (CDDs). They are calculated by subtracting the mean outside daily temperature from 18 degrees Celsius, and summing up only positive values over a fixed period or summing up negative values. 18 degrees Celsius is used because it is assumed that additional heat generated by building occupant raises the indoor temperature to 21 degrees Celsius (Sivak, M, 2013). We know the preferred temperature is 21 degrees Celsius – read our blog about the ideal temperature and productivity and well-being.
In America, research has shown that Minneapolis which is the coldest state HDDs are 1.8 times that of CDDs for Miami. In the UK, we don’t have the Miami climate. In the UK, the warmest town on record was Faversham in Kent which as reached 38.5 degrees Celsius in 2003, yet the average monthly temperature for Faversham in 2017 was 12.3 degrees Celsius. The the coldest place is Braemar, Aberdeenshire which reached -27.2°C in 1995 and the average monthly temperature in 2017 was only 3 degrees Celsius! That’s a lot of heating energy! In reality, the UK only rises above 18 degrees Celsius for four months of the year on average, so you would think that we don’t have to worry too much about cooling, That’s not true, read right to the end of this article …
The Building Energy Management System (BEMS)
Boss Controls offers an energy audit service which is based on the BS EN 15232 standard using the Siemens Building Technologies BS EN 15232 predictive tool which identifies where significant savings can be made.
With this service we take a proactive approach focusing on key areas of energy wastage i.e. time zones, set points, deadbands, conflicts between heating and cooling, overridden plant running in hand, poorly designed control strategy.
Following on from this, we will provide a detailed report summarising our findings and actions which can be taken to further optimise the control system and reduce energy, offering a healthy return-on-investment.
Looking at the bigger picture, we need to think holistically; we need to think planet: Global power consumption for air conditioning is predicted to increase by 33% by 2100 because developing countries also want to enjoy artificial cold comfort (Guardian, 2015). Human comfort is killing our planet.
The energy source
Air conditioning is mainly powered by electricity from burning fossil fuel. Increased use of air conditioning increases global warming and the result is a vicious cycle. Heating is powered by a mix of energy resources, some of which are kinder to the planet.
Old cooling and heating equipment varies in efficiency; an energy audit will pick up the energy efficiency of your heating and cooling and buildings can be retrofitted with energy efficient equipment.
“Energy savings obtained by HVAC systems vary greatly, depending on the layout, setup, and purpose of the system. Savings over 20% for forced air systems are reported.” (Sung et al. 2011; Olivieri et al. 2014; Tanner et al. 2013; Henze and May-Ostendorp 2012).
The UK is a cooler climate and therefore more energy is is demanded by heating, however, if we keep looking inwards we will be in for a shock. You only have to look at the rise in floods and tropical storms to understand that human behaviour has has a profound effect on global warming.
Back to cooling; globally, energy required to power cooling is on the rise and expected to use more energy than for heating within the next 82 years – and as air conditioning is now considered a human right, this may happen more quickly than predicted. Faulty air conditioners can also emit hydroflourocarbons (HFCs) which trap heat in the atmosphere at a much higher rate than carbon dioxide, increasing the rate of climate change.
Call Boss Controls on 01403 886508 today, or use the contact form below, to book an energy audit and improve your energy efficiency, which will also improve staff well-being, increased productivity and reduced energy costs.
- Sivak M, (2013), Air conditioning versus heating: climate control is more energy demanding in Minneapolis than in Miami, Environ. Res. Let . 8 014050
- Henley, J (2015), World set to use more energy for cooling than heating, [cited 25/2/18, https://www.theguardian.com/environment/2015/oct/26/cold-economy-cop21-global-warming-carbon-emissions]