Manufacturing any product requires energy and with consumer packaging these levels can be significant. The fuel used either directly, or via electricity, has a MASSIVE impact on the final footprint of a piece of packaging.
This is highly relevant when we import materials which have been made with coal fired electricity compared to wind generated electricity. Steel and aluminium are both imported from outside Europe, so recycling and remaking locally has a double win.
Energy sources and carbon emissions
Oil, coal, gas are primarily used globally to fulfill this need, but add significantly to the carbon impact. Renewable energy sources provide huge savings. The carbon emissions generating electricity from wind power are 200 times less than coal fired generation (see statistics on carbon emissions below).
Fossil fuel emissions
The carbon footprint of fossil fuelled power plants is dominated by emissions during their operation* i.e. when things are made. Indirect emissions during other life cycle phases such as raw material extraction and plant construction are relatively minor
- Conventional coal combustion systems result in emissions of approximately 1kg of CO2 per kWh
- Coal burning power systems have the largest carbon footprint of all the electricity generation systems (UK POSR)
- Oil-fired electricity result in emissions of approximately 0.65kg of CO2 per kWh.
- Oil accounts for only a very small proportion (1%) of the electricity generated in the UK. It is primarily used as a back-up fuel to cover peak electricity demand periods. (UK POSR)
Renewable energy emissions
In contrast to fossil fuelled power generation, the common feature of renewable energy systems is that emissions of greenhouse gases and other atmospheric pollutants are ‘indirect’ i,e building, maintaining and disposing.
- Combustion of low density fuel results in higher life cycle emissions at 0.093 kg CO2 per kWh
- Gasification of higher density wood-chip at 0.025 kg CO2 per kWh (UK POSR)
Photo voltaic cells
- Life cycle CO2 emissions for UK photo-voltaic power systems are currently 0.058 kg CO2 per kWh. Southern European ones, due to more sunlight are at 0.035 kg CO2 per kWh.
- The silicon required for PV modules is extracted from quartz sand at high temperatures. This is accounts for 60% of the total energy requirement (UK POSR)
- There are two types of marine energy devices; wave energy converters and tidal devices
- Most CO2 is emitted during manufacture of the structural materials
- A wave converter device presently requires 665 tonnes of steel. Life cycle emissions for this type of marine technology is estimated between 0.025-0.05 kg CO2 per kWh (UK POSR)
- There are two main types of hydroelectric schemes
- Storage which needs dams and
- Run-of-River, turbines placed in the river.
- Storage schemes have a higher footprint at 0.01 to 0.03 kg CO2 per kWh
- Run-of-River schemes have the lowest footprint of all renewables at less than 0.005 to 0.03 kg CO2 per kWh (UK POSR)
- Electricity generated from wind energy has one of the lowest carbon footprints. Onshore farms are 0.00464 kg CO2 per kWh versus offshore
0.00525 kg CO2 per kWh.
- Production of steel for the tower, concrete for the foundations and epoxy/fibreglass for the rotor blades account for 98% of the total life cycle CO2 emissions (UK POSR)
Nuclear energy emissions
Like renewable energy sources, the common feature of nuclear energy systems is that emissions of greenhouse gases and other atmospheric pollutants are ‘indirect’,
- Nuclear power generation has a relatively small carbon footprint of ~0.005 kg CO2 per kWh.
- Most emissions occur during uranium mining, enrichment and fuel fabrication. Decommissioning accounts for 35% of the lifetime CO2 emissions (UK POSR)