Solar energy in uae review and future prospects

Course: EENG 515

Section: A

Semester: Fall 2016/2017

Submitted by: Tarek Kamar Bilal Abou Ghoushe

Supervised by: Dr. Mohamad Abu Chahine

Solar energy in UAE: Review and Future prospects

Date: 09-01-2017

1. Introduction:

United Arab Emirates (UAE) is known for its large oil and gas reserves, but since 2006, it has been involved in various unprecedented activities in the renewable energy sector. Those activities are driven by: a rapidly increasing energy and water demand as a consequence to a rapid population growth and economic development. Also there is a governmental desire to maintain a strong position in the world energy market, necessity to diversify in oil-based economy, and a sense of moral responsibility towards the planet.A good exposure to the sun justifies why solar energy has dominated those activities.

2. Objectives:

The aim of this research is to review and build on the existing knowledge to assess whether solar energy can be an essential part of UAE’S energy mix. We present this research work in four parts. First, we assess the solar energy resource by reporting results from different studies. In a second part, we will discuss the environmental operating conditions of solar installations and how that affects the performance of various technologies. In a third part, we will see the benefits of solar energy to the transportation, electricity production sector. In the last part, we will discuss Renewable Energy Map analysis in 2030 in UAE.

3. Methods for evaluating the solar resources

3.1 Artificial Neural Networks : In UAE, the temperature, humidity, wind, and sunshine duration measurements have been recorded by Assi among 1995 to 2007 in Al- ain city in order to predict the global solar radiation using artificial neural networks. Artificial neural networks (ANN) is a computation technique consists in finding the patterns in a known set of input data based on these patterns a set of unknown data can be estimated. Five models with different combinations of input data were developed as the following list [1]:-Sunshine duration, temperature, wind speed, and humidity-Sunshine duration, temperature, and wind speed-Sunshine duration, temperature, and humidity-Sunshine duration, wind speed, and humidity-temperature, wind speed and humidityThe models were developed to estimate the monthly average values of global horizontal radiation (GHI). For all models, it was found that the coefficients of determination (R²) were above 0.87, the root –mean square error (RMSE) values varied between 0.276 and 0.391 and the mean bias error (MBE) values ranged between -0.00014 and 0.00009 (as shown in table 1).

Table 1- ANN used for estimating global irradiation parameters in the UAE [1].

Assi and Al. have used this technique for estimating global solar radiation in Abu Dhabi & Al Ain city using sunshine duration measurements from 1995 to 2007. Highest coefficients of determination were 94 % in Abu Dhabi and 84% in Al Ain City.

3.2 Remote sensing techniques by processing satellite data:Eissa and Al. have focused on studying the characteristics of the atmosphere (humidity, airborne dust particles) and their effect on the incident solar radiation [1]. Model Heliosat -2 was used, input parameters were the monthly Linke turpidity factor normalized to Air Mass 2 (AM2) and cloud index taken from 7 weather stations in UAE and Meteo satellite. The Linke turpidity factor normalized to AM2 was used for estimating clear sky global irradiance (GHI) and direct normal irradiance (DNI). The irradiance measured onboard of the satellite was used for determining the cloud index this will enable the estimation of GHI (as shown in figure 1&2).

Figure 1- GHI map obtained by processing satellite data [1]

Figure 2- Yearly DNI map obtained by processing satellite data [1]

4. Effect of local environment operating conditions on the performance of different technologies

4.1 Attenuation and scattering of sunlight: UAE environment is characterized by high concentrations of air bone dust particles and high humidity, which tend to diffuse and attenuate the intensity of solar irradiance. Eissa and Al. have reported that during heavy dusty days ground measurements devices provide underestimate values of DNI and GHI because of the accumulation of dust on sensors. The use of satellite data is more reliable to achieve more accurate estimations [1]. Parajula and Al. reported that Atmospheric Optical Depth (AOD) is related to topography, wind, speed, soil moisture, surface roughness, and soil properties [1]. The concentration of dust AOD in the atmosphere is both location dependent(topography, soil moisture, surface roughness) and time dependent (wind speed, soil moisture).Parajula have studied the effect of soil moisture and wind speed in AOD in 2 areas in Abu Dhabi desert(Meziana /Hamim). It was found that the months of May to September witness the highest magnitude of AOD in both areas (as

shown in figure 3&4). It was realized that for the same area and same month of year AOD may vary from one year to another.

Figure 3- Maximum values of the global horizontal irradiance (GHI) Direct normal irradiance (DNI) [1]

Figure 4- Monthly average GHI and DNI values [1]

4.2 Sun shape profile: The forward scattering of sun rays by atmospheric particles causes the formation of a region around the solar disk called circumsolar / sun areole.DNI measurements devices have a larger acceptance angle than concentrating receivers. They capture a larger portion of incoming radiation not only from solar disk but also from circumsolar region. The actual DNI that is incident on the receiver of an optical concentrator is rather estimated. The sun shape of solar disk is drawn in Abu Dhabi [1]. Two parameters were used to quantify this effect:-CircumSolar Ratio (CSR) which is the radiant flux contained in the incident radiation coming from the solar disk & surrounding region.- Intercept factor (IF): It is a fraction of radiation incident on the absorbing surface divided by total radiation that can be possibly received at the receiver.In order to study this effect in the dusty environment of UAE, Kalapatabu et Al. have developed a device called sun shape rotating radiometer (SR²) and simulation models to estimate the circumsolar radiation profile and intercept factor [1]. In order to see the effect of these parameters on the performance of concentrating solar system, values of the CSR and IF during a dusty and a clear day were estimated by Kalapatapu et Al. and they are shown in Fig 5 & 6. From both figures, we see that the CSR affects the intercept factor, and therefore, the amount of energy received at the receiver. For instance in Fig 6, we see that the intercept factor drops by 4-12 % absolute, which means around 4-12 % less radiation is received in a dusty day compared with a clear day.

Figure 5- Estimated values of the circumsolar ratio (CSR) during a clear and a dusty day[1].

Figure 6- Estimated values of the intercept factor during a clear and a Dusty day [1].

5. Main solar plant power plants in UAE and their benefits:

5.1 Masdar 10 MW PV power plant:

This power plant was officially inaugurated in June 2009 and was designed and constructed by Enviromena®. This plant has an area of 218,000 m² with 87,336 PV modules installed on light weight steel racking and 200 km of wiring It is producing about 175,000 MWh of electricity per year. This makes it the first, and by far, the largest grid connected solar PV plant in the Middle East and North Africa. There are two types of solar PV module technologies being used in this power plant: crystalline silicon modules (18,288 units) to supply around 5 MW and CdTe thin film modules (69,048 units) to supply around 5 MW (check figure 7) [1].

5.2 Shams 1 Concentrated solar power plant 100 MW: Shams 1 extends over an are of 2.5 km² with an approximate capacity of 100 MW.The solar fields consists of 768 parabolic through collectors supplied by Abengoa Solar. This project generates efficient solar thermal electricity from concentrating sunlight by parabolic mirrors to heat a fluid which generates a high pressure steam to drive a conventional steam turbine. Shams 1 plant will offset about 175,000 tone of CO2 per year, which is equivalent to planting 1.5 million trees or removing 15,000 cars from the roads of Abu Dhabi (check figure 7) [1].

Figure 7- The solar installation map for the UAE [1]

5.3 Masdar city’s transportation: Masdar city has now its own electric car infrastructure which consists of 13 conventional electric vehicles and another 9 self-driving electric vehicles, all powered by solar energy generated in the city [1]. While the self-driving ones circulate inside the city only, the conventional ones move around Abu Dhabi city and its surroundings in the context of a pilot project which aims at building a larger infrastructure of electric vehicles in Abu Dhabi. - This transportation infrastructure can be used for energy storage in the city when the solar installations are generating less power than required. The goal is to make Masdar Institute Campus in the city energy independent by putting the extra energy generated by roof top solar installation in the batteries of electric vehicles and take it back when needed. Following Vehicle to Grid (V2G) approach: energy production by

solar installation and energy consumption in the campus was built, and the results suggested that up to 7 hour of storage can be provided by using the existing vehicles.

6. Renewable Energy Map (Remap) analysis in 2030 in UAE:REmap 2030, a global roadmap project by the International Renewable Energy Agency (IRENA), examines the realistic potential for higher renewable energy uptake in a variety of countries and markets. This country-level analysis covers all parts of the UAE’s energy system, including power, industry, buildings, and transport [2]. Importantly, REmap 2030 benchmarks against alternative sources of supply like natural gas, oil, coal, and nuclear power, using a combination of local and international cost data. The analysis takes a moderate approach: the first case assumes USD 90/barrel oil and USD 8/MBtu natural gas (below current UAE marginal gas prices), the second assumes USD 120/barrel oil and USD 14/MBtu gas (similar to recent UAE marginal gas prices) [2]. While the price of oil has fallen by around 50% since mid-2014, the gas price is the more critical reference for renewable energy competitiveness in the UAE – and remains consistent with the analysis assumptions even as of early 2015. Solar is the critical resource and focus for the UAE. Different forms of solar energy would account for more than 90% of renewable energy use in REmap 2030.

6.1 Power sector: REmap 2030 evaluates the potential of six renewable technology options in the power sector: - Solar PV (utility-scale)- Solar PV – rooftop -Solar PV for Reverse Osmosis (RO) desalination- Landfill gas - Wind onshore-Solar CSP parabolic trough (PT) with Thermal Energy Storage. Collectively, they are estimated to provide 25% of power output by 2030. The REmap Options also explore and suggest resolution of the critical linkage between power and water production. Electricity consumption is expected to increase substantially between now and 2030. Despite efforts to diversify the energy mix with large-scale renewable energy, clean coal and nuclear power projects (all on the horizon), the UAE will still be overwhelmingly dependent on natural gas cogeneration to produce electricity and desalinated water in the future. However, with the declining cost of renewable energy, and the feasibility of RO increasing, utility-scale renewable energy plants and large or commercial rooftop PV make economic sense for the utility if policies can be put in place to support this. Viewed as fuel extenders or savers, the installation of renewable energy capacity will allow an easier transition to higher imported natural gas prices, especially after the current Dolphin project4 is up for renegotiations in 2032. As electricity is linked to all of the above mentioned sectors in the UAE, diversifying electricity production

is vital in order to prevent shortages or out- ages in the future. The contributions of each technology are shown in table 2.

Table 2- Renewable power generation breakdown, 2010 and REmap 2030 [2]

The deployment scale of renewable technologies in the Reference and REmap 2030s is contrasted in Figure 8. While in the Reference Case almost all renewable energy is in the power sector, in the REmap 2030, the share of renewable-sourced heat (also used for cooling) increases from 6% to 43%. However, renewable power is still the largest source of renewable energy, with solar PV making up over 40% of all renewable energy, followed by solar thermal heat with over one-third, and CSP with 12%. Solar energy collectively makes up 90% of all renewable energy in REmap 2030, with the remaining 10% provided by geothermal heat, wind power and waste-to-energy systems[2].

Figure 8- Renewable energy deployment by technology in 2030: Reference Case and REmap 2030 [2]

Figure 9 additionally illustrates the implications for generation capacity, and compares them to the Reference Case. Notably, solar PV installations jump from 1.6 GW to 21 GW, and solar CSP expands from 1.3 GW to 5.8 GW with new CSP including thermal energy storage. The reduction of 5.5 GW in natural gas capacity is offset entirely by dispatchable CSP. While the capacity additions are significant, they are economically justified by the savings on fossil fuel costs. It is notable that there is no additional coal and nuclear capacity.

Figure 9- Power capacity breakdown in 2030: Reference Case and Remap [2]

REmap 2030 shows not just gains in renewable energy deployment, but also major reductions in domestic consumption of oil and natural gas. Oil consumption namely through deployment of vehicle and freight alternatives drops a sizeable 8.5% in REmap 2030 compared to the Reference Case in 2030. This is especially relevant given the UAE’s role as one of the world’s largest oil and oil product exporters. Some portion of that ‘liberated’ oil could potentially be channeled into the UAE’s export stream, generating substantial new revenue for the country. On the gas side, REmap 2030 estimates reductions of 16% in domestic consumption. While rapid demand growth in the UAE means that repurposing of these savings for exports is less likely, the potential for avoidance of additional gas imports is significant especially with marginal costs of imports temporarily as low as USD 9-10/MBtu and more recently over 12/MBtu (see figure 10)Savings in fossil fuels directly translate into mitigation of CO2 emissions compared to the Reference Case in 2030. According to Figure 11 34 Mt of CO2 can be avoided annually in 2030 as the share of renewable energy in the TFEC increases to 10%. This is equivalent to 13% reduction in CO2 emissions in the total energy system of the UAE in 2030 over the reference case [2].

Figure 10- How renewables can offset fossil fuels in 2030 Reference Case and Remap [2]

Figure 11- CO2 emission reductions based on REmap Options [2]

7. Conclusions:

In 2030, the UAE would have a minimum daily demand of 14 GW (e.g., during a winter night), and a peak of 30+ GW during a summer day when cooling requirements are highest. While solar PV prices have drastically changed since then, perceptions among policymakers and the resulting strategies have not moved at the same pace. The price reductions assumed to be reached by 2020 or even 2025 at the time have in fact arrived in 2014.

The economic rationale would hence dictate that 2030 targets are attractive for 2020, and that 2030 targets should be higher. UAE may in fact be economically best off to encourage demand to move to the peak to utilize the lower-cost solar resource, which would shift the current grid-management paradigm. Solar could not only cover peak demand but potentially even meet minimum power requirements during daylight hours.

References:

1- Alaeddine Mokri, Mona Aal Ali, Mahieddine Emziana. December 2013 .Solar energy in UAE: a review. Elsevier. [updated 2013 16 July; accessed 2013 August 29];Volume(28): ISSN: 1364-0321 http://www.sciencedirect.com/science/article/pii/S1364032113004838

2- Irena. April 2015.c2015. Abu Dhabi-United Arab Emirates: Masdar Institute of Science and Technology; [accessed 2015 March]. http://www.irena.org/remap/IRENA_REmap_UAE_report_2015.pdf