INTERNATIONAL NEWS
INCORPORATING COLD CHAIN
medical supplies, will improve health
outcomes, reduce food and vaccine
loss, and also build capacity to respond
to future shocks.”
Transitioning to high-efficiency
cooling can more than double the
climate mitigation effects of the HFC
phase-down, while also delivering
economic, health, and development
benefits. Refrigerant conversions driven
by the Montreal Protocol have already
catalysed significant improvements in the
energy efficiency of refrigeration and AC
systems – up to 60% in some subsectors
(Shende 2009).
Lessons learned from past transitions
show that manufacturers who invested
in improving the efficiency of their
products as part of redesign for the
CFC and HCFC transitions benefited
from policies to improve the energy
efficiency of cooling equipment that
resulted in reductions in lifecycle costs to
consumers, drove high-volume sales, and
even reduced first costs.
While similar improvements are
expected under the HFC phase-down,
more-deliberate policy efforts can drive
even greater efficiency improvements.
With emission reduction potential in
general, it is difficult to estimate GHG
emission reduction potential precisely
from increased energy efficiency
because avoided emissions depend
heavily on the assumptions made about
the decarbonisation rate of the global
economy (including its electricity system)
due to other mitigation efforts.
A number of key studies offer insights into
the potential enhancements available
and according to these studies, the world
can avoid the equivalent of up to 210460
GtCO 2
e - roughly equal to 4-8 years of
global emissions at 2018 levels – over the
coming four decades through efficiency
improvements and the refrigerant
transition.
The Food and Agriculture
Organization of the United Nations
(FAO) estimates that food losses
and waste cause up to 8% of total
greenhouse gas emissions, and cost
up to USD2.6-trillion per year, including
USD700-billion of environmental costs
and USD900 billion of social costs.
Meanwhile, in 2018, 821.6 million people
worldwide were undernourished.
The lack of adequate cold chains
is responsible for about 9% of lost
production of perishable foods even
in developed countries and 23% in
developing countries. Project Drawdown
estimates that reduced food loss and
waste brought about by consumer
behaviour change and improved cold
chains and agricultural practices would
avoid 93.7 GtCO 2
e of emissions between
2020 and 2050. The potential impact
of improved cold chains alone could
account for 19-21 GtCO 2
e of these
avoided emissions.
This article is an extract of the report
available from the United Nations
Environment Programme. CLA
Renewable energy model
offers endless potential
ShutterStock
As a first-of-its-kind software solution it
calculates various renewable
energy data, and as a major
bonus, it is open source.
One of the pressing topics particularly in
the cold chain is the evaluation, use and
implementation of alternate energy as a
solution to provide a complete system in
remote areas and developing countries as
the preservation of perishables become
more urgent and in many instances, critical.
What can the Renewable Energy
Potential (reV) model calculate when it
comes to renewable energy potential?
Just about everything. This novel modelling
framework includes highly dynamic,
user-defined modules that function at
different spatial and temporal resolutions,
allowing users to assess resource potential,
technical potential, and supply curves at
varying levels of detail for photovoltaic
(PV), concentrating solar power (CSP),
and wind turbine technologies.
Available now open source (the ability
to use, distribute and make changes freely
without permissions or legal infringements)
the reV model was developed by
researchers from the National Renewable
Energy Laboratory (NREL) to align
previously disparate analyses for resource
modelling, technical potential, and
renewable energy cost supply curves.
"No other renewable energy potential
model exists of this scale, fidelity, and
flexibility," says Galen Maclaurin, manager
of the NREL geospatial data science group
that developed the model. reV provides
invaluable insight for utility planners,
regional and national agencies, project
and land developers, and researchers.
ENABLING SCALABLE
SPATIOTEMPORAL ANALYSIS
The reV model can assess renewable
energy potential for a single site up to an
entire continent at temporal resolutions
ranging from five minutes to hourly,
spanning a single year or multiple decades.
The model has been run across North
America, South and Central Asia, the
Renewable energy is an immediate solution to complete the cold chain for remote or
rural areas without access to conventional power sources.
ShutterStock
Middle East, South America, and South
Africa to inform national- and internationalscale
analyses as well as regional
infrastructure and deployment planning.
The land exclusion module in reV
considers technical barriers, regulatory
restrictions, or stakeholder constraints
to land access for renewable energy
projects so developers know where to
focus their efforts.
MODELLING SYSTEM
PERFORMANCE WITH HIGH-VALUE
DATA SETS
Coupled with NREL's System Advisor Model,
the reV model's generation module
estimates system performance based
on user-defined parameters like panel
tilt angle and inverter load ratio for PV
systems or hub height and rotor diameter
for wind systems.
Through efficient parallelisation, the
reV model reads hundreds of terabytes
of time-series solar or wind data from
state-of-art resource data sets, including
the National Solar Radiation Database
(NSRDB) and the Wind Integration
National Dataset (WIND) Toolkit, which
both recently became available on the
Open Source software allows users to
add, edit or incorporate specific coding
free of charge and without any legal
contraventions.
cloud, expanding accessibility to the
average user.
CALCULATING COST AND
CAPACITY
The reV model estimates for wind
and solar sites the levelised cost of
electricity (LCOE), which represents the
average revenue per unit of electricity
generated needed to make up for
the costs of building and operating a
generating plant.
Based on LCOE and accessibility to
transmission, the reV renewable energy
supply curve module ranks sites based on
which ones to develop first, again helping
developers to know where to focus their
efforts or eliminate potential sites.
OTHER MODELS IN THE REV FAMILY
Several other open-source tools can
integrate with reV. The reV Exchange
Model (reVX) can be used after reV
processing to couple with capacity
expansion and production cost models.
Additionally, the Resource Extraction Tool
(rex) assists with user accessibility to the
state-of-art resource data sets integrated
into reV.
CLA
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www.coldlinkafrica.co.za COLD LINK AFRICA • September 2020