Biomass (Food Waste) in Residential Cooling and Heating Sector of the Kingdom of Saudi Arabia (KSA)
Abstract
Initially, waste management was used to minimize waste volumes and
maintain good standards of hygiene. Over the years, the idea of waste
management evolved, with principles like waste-to-energy, waste reduction and
waste recycling. Besides, due to the high demand and huge need for energy,
which is considered one of the most basic aspects for all governments, the
considerable amount of waste produced and dumped in landfills underlines the
need to use biomass, especially waste, as a source of energy.
Waste-to-energy technology (WTET) is a method of recycling waste by
transforming its chemical materials to use as a source of energy, like heat and
power. One of those technologies is anaerobic digestion (AD), which is used to
treat organic waste, for example food waste, to produce biogas, which can be
used for producing electricity and heat. AD generates clean and safe energy,
which can reduce both the amount of food waste in landfills and the release of
greenhouses gases (GHG) while producing energy.
The population in Saudi Arabia (KSA) is increasing at 3.4% every year,
and is forecasted to reach around 49.9 million in 2030. Also, the KSA 2030
VISION aims to increase the number of visitors for Hajj and Umrah, reaching
6 million and 30 million, respectively. Therefore, the amount of waste will
directly increase, and it is predicted to reach around 26.2 × 106
𝑡𝑜𝑛𝑛𝑒𝑠 in 2030,
while the food waste, at 13.21 × 106
𝑡𝑜𝑛𝑛𝑒𝑠, will be 50.6% of total waste.
The outcomes from AD were estimated in this study under four different
scenarios; the scenario without any reduction in the waste has the highest
result, producing 52,504.2 TJ as energy potential and 0.58 GW actual power,
which can meet 19.3% of the 2030 VISION of producing 3 GW from WTET in
2030. In addition, the amount of power used for cooling (air-conditioning – AC)
purposes in general in the KSA is around 60% of the total consumed electricity
in the residential sector. Also, the total power consumed by heaters is 0.74 GW
in the residential sector. It is possible to produce 77.98% of that power from
using AD in the first scenario, whereas from an economic view the AD outcome
with the highest value is the first scenario, with total a gross revenue
of 8,472.75 Million per year and it is found that using AD has a high potential
for cooling and heating purposes.
To achieve the sustainability objective of reducing the waste in KSA by
2030, it is recommended to use WTE technology (AD for food waste) with
recycling the other types of waste. As a result, there are many advantages of
using waste biorefineries in Saudi Arabia, which will help with the
unemployment problem, drive R&D in the renewable energy sciences, and
reduce both the need to use oil to produce energy and the dumping of waste in
landfills; therefore, GHG emissions will decrease.