Energy
Power boost from
bio-energy
Creating greener sources of
energy as well as finding
alternative and more
environmentally-friendly
methods for waste disposal are challenges
facing all countries across the globe.
The traditional reliance on fossil fuels
is lessening, as green energy sources
are now being increasingly harnessed.
However, many experts state that the
world still has a long way to go in order to
meet targets set out at the Paris Climate
Agreement.
The problem of waste is equally as
challenging, because even with increased
recycling, civilisation will always create
some sort of waste that will need to be
disposed of.
One solution to both of these
challenges is anaerobic digestion (AD),
which is recognised by the UK and Irish
governments, Defra, the Welsh Assembly,
the Scottish Parliament, Friends of the
Earth and the National Farmers Union as
one of the best methods for food waste
recycling and dealing with farm waste and
sewage sludge.
AD processes plant materials (biomass)
using bacteria, which digest biomass and
produce biogas as a by-product.
Biomass includes anything that is plantderived;
municipal solid waste, manure,
crop residues, compost, food waste, paper
and waste water.
The biogas can then be used as a fuel
in a CHP (combined heat and power)
unit to generate renewable energy, such as
electricity.
Interestingly the use of biogas is not
new. It has been used in the UK since 1895,
when gas from sewage was used in street
lamps across the city of Exeter.
Another benefit of AD is that whatever
is left over from the process is a nutrient
rich bio-fertiliser which can be pasteurised
to kill any pathogens and then stored in
large covered tanks ready to be applied
twice a year on farmland in place of fossil
fuel derived fertilisers.
It has been estimated that every tonne of
food waste recycled by anaerobic digestion
as an alternative to landfill prevents
between 0.5t and 1t of CO2 entering the
atmosphere.
There are currently more than 100 AD
plants in the UK at present and more than
14 in the Republic of Ireland. The number
is expected to grow in the coming years
and one that is due to come into operation
next year is at Huntstown on the outskirts
of Dublin.
Ireland’s investment in green energy and waste solutions
continues with the construction of a renewable bio-energy
plant near Dublin.
FACT FILE
Huntstown Renewable
Bio-Energy Plant,
Dublin
Main client:
Viridian
Main contractor:
Priority Construction &
Jones Engineering jv
Structural engineer:
DBFL Consulting
Engineers
Steelwork contractor:
Fox Bros. Engineering
Steel tonnage: 200t
20 NSC
March 19