What Planet Are You On?'s energy and transport expert, Prof. J.J. Leahy is an Environmental Chemist at the School of Chemical Science, University of Limerick. Here, he explains how to cut down on energy waste at home.

What Planet Are You On? offers an opportunity to present a global challenge from the perspective of families living ordinary lives. Energy and how we consume it is fundamentally altering the geography and biology of the planet, and the speed and manner in which we adapt to these changes will have consequences for all of us.

Energy consumption is generally higher in richer countries than poorer and is related to our lifestyles and our real and perceived needs.

How much energy do we use at home?
In this programme, through the eyes of the families, we get insights into how our energy consumption is determined by our lifestyles, and as the ultimate consumers of energy, it shows us how we can make changes which can reduce our carbon footprint and have a positive impact on climate change.

Within our houses, we consume a quarter of the energy used in Ireland generating a quarter of the energy-related CO2 emissions (LINK). From 2006 to 2014, there were significant reductions in the CO2 emissions from our homes, primarily due to a shift from coal/oil to gas heating, but this was reversed from 2014 to 2016, probably due to people having more money to spend (LINK)

Thankfully, we are on a downward trend again as people become aware of climate change and are taking greater personal responsibility. This was really noticeable with our families, they all want to change.

Where can we make changes?
Within the scheduling of the programme, we focused on electricity usage within the home and transport outside the home. Space heating and its potential wastage weren't included as the temperature was mild over the filming period.

Home heating
For most homes, heating can have almost three times the carbon footprint of electricity. The Commission for Regulation of Utilities (CRU) suggests that the average Irish household uses 11,000 kW/h of gas and 4,200 kW/h of electricity each year.

Actual energy usage differs depending on the size of the home and how many people live there, as well as other factors like whether the house is occupied during the day or not. Some of the families used more (6200 kW.h for the McKevitts).

The 4,200 kW/h of electricity used by a typical Irish household compares with 4000 kW.h for the EU average but we compare poorly against the Netherlands who consume 3100 kW.h. 

Utilities
I think people will be surprised to learn how much energy they consume in their tumble dryers, (more than twice that of their washing machine). Probably in Ireland, we wash our clothes more than is necessary because the tumble dryer provides us with a very convenient way of drying clothes.  

Electricity is not the major culprit as between 2005 and 2016, electricity use in households increased by 5%, but the associated CO2 emissions decreased by 20%. But this was due to reasons outside our personal control and is mostly due to the replacement of coal and oil with natural gas as well as greater penetration of wind on the electricity grid.

Transport
All of the families who participated in the show were aware that their cars were the biggest contributors to their carbon emissions but I think they were surprised to learn that it was 5 times greater than that from all electricity usage in the home.

For the two rural-based families, the Gannons and McKevitts, this was not surprising as their commutes to work were very long and there was no public transport alternative. Public transport between rural and urban centres is appalling. And for these families, the electric car had a large effect in terms of reducing their carbon footprint.  

However, I was surprised by the extent to which our Finglas family used their car (450km/week) as Dublin has supposedly the best public transport infra-structure nationally. This was not due to lack of willingness but it was severely inconvenient.  A normal 35-minute car journey took 1 hour 40 to complete when taking the bus due to a lack of connectedness. 

Going forward
For our families, the challenge will be to maintain a realistic reduction in energy-related carbon footprint while maintaining many aspects their lifestyles but for all of the change is going to involve some pain if we are to change. These families will provide inspiration through their humour and persistence.

Watch What Planet Are You On? on RTÉ One.