Smart Grid: Reconstructing Primitive Infrastructure
It comes as no surprise that the total generation of electricity in Bangladesh can barely cover local demand, let alone be exported. But what if I told you there is a way you can not only meet your demand for power, but also give back to the power grid yourself? Don’t worry, this isn’t clickbait. Thanks to an efficient technology called “Smart Grid”, electricity is smarter than ever before. With an efficiency that is evidently greater than the existing power system- why hasn’t everyone shifted to Smart Grids yet?
Let’s start by acknowledging what challenges we face at present. In 2019, the electricity coverage in Bangladesh was 95%, and the installed total capacity was 20,000 MW [1]. Although these figures might be exaggerated, there is no denying that the deficit between demand and generation is a serious issue, and it will only escalate with time. Bangladesh will need an estimated 34,000 MW of power by 2030 to sustain its economic growth of over 7 percent [2]. At present, about 62.9% of generated electricity comes from natural gas, while only 3.3% is from renewable sources. Do you see something disturbing here? We are heavily dependent on a source that will run out in the next 10–12 years [3]. According to State Minister for Power, Energy, and Mineral Resources, “Currently, the reserves [till Jan 1, 2020] stand at 10.63 trillion cubic feet with a 2.57 billion cubic feet being extracted daily. If the current rate of exploitation persists, the reserves can only be used for 11 more years, which means until 2031” [4] It is high time we follow the footsteps of the technologically advanced countries and shift our focus from natural gas to renewable sources, partially if not completely. “Partially” is a term I want to emphasize here. This “Partial Dependence” on renewable sources is exactly what we are going to talk about today.
What is a Smart Grid?
Smart Grid is the next chapter in the efficient distribution of energy. By definition, a smart grid is an electrical grid that performs a variety of operations in power generation, transmission, and distribution including technologies like smart meters, smart appliances, renewable energy resources, and bi-directional communication between the utility and the customers. The “Grid” refers to the electric network of transmission lines, substations, and transformers that deliver electricity from the power plant to your house.
A grid connects your distribution board to the transmission lines that carry electricity. So, what is so “smart” about the “smart grid”? The main feature of a Smart Grid is the bidirectional flow of information which is obtained through sensing, monitoring, adapting, and decision making along the transmission lines and distribution boards. Your distribution network will know when to consume power and when to supply it based on this information. Now let’s go deeper into each constituent.
Firstly, we’ll look into the generation and transmission of electricity. Solar panels are not widespread just yet. But remember how I emphasized “Partial”. Well, it is now or never that we start accommodating solar panels (also known as photovoltaic cells, PV for short) in our power systems. Solar panels alone might not suffice for your daily electricity demand, that’s why smart grids can help strike the perfect balance between partial dependence on PV and the central grid. At peak demand time, the grid along with the PVs supply power to the loads. Usually, the deficit power of PV will be compensated by grid power. Figure 2.a shows the power flow diagram from both PV and Grid to Load.
Next, an obvious risk associated with PVs is what if there is no electricity generation because of bad weather or night time? Well a smart grid will sense when the PV is producing less than the minimum amount needed, and then it will deactivate the PV completely and take its whole supply from the grid.
Next, the most interesting part. When your PV is generating more power than your loads need, all domestic demand is compensated by the PV alone, but what happens to the remaining power? Well, in this fight for efficiency we certainly can’t afford to waste energy. That is why the excess power from the PV is directly fed into the grid itself! Can you imagine, you will be a supplier of electricity to the transmission lines of the country! This is the key point about how the electricity distribution is accomplished with high efficiency.
Last but not the least, the fourth mode of operation is when supply is disrupted due to damage in the transmission lines. Theoretically, you should still be able to use power from your PV but in this mode of operation, all power sources are completely cut off. This is because the excess power from the PV will get supplied to the grid, and in case that happens, the transmission line cannot be repaired by linemen (risk of electrocution).
What is the bi-directional flow of information?
So, how does this bidirectional flow of information happen? How does the Smart Grid know when to consume power and when to supply it? It is done with the help of a smart metering system. A meter that keeps track of the incoming and outgoing power is known as the “Netmeter”. The net meter collects consumption rates at fixed time intervals. This information can be used to determine the peak demand profile. Since lowering the peak demand and smoothing demand profile reduces overall plant and capital cost requirements, in the peak period the electric utility can use real-time pricing to convince some users to reduce their power demands, so that the total demand profile full of peaks can be shaped to a nicely smoothed demand profile [5].
Also, the netmeter can introduce a credit system. When the consumer is receiving power, the meter will store how much power is consumed. But when PV is supplying power to the grid, it’ll be considered as negative consumption, so the bill will be reduced according to the net amount. To avoid complications, if net consumption becomes negative, the extra power supplied can be considered as credit, and that can be deducted from the next billing cycle. This is a win-win situation because the consumer is saving money and the supplier is saving energy with increasing efficiency.
“Is the smart grid really a smart idea?”
So, with all the advantages stated above and a few more, what’s stopping people from opting for a smart grid? Well, the biggest reason is that it is expensive to tear down the existing infrastructure and make a system for bidirectional power flow. Also, installing Solar panels comes with external costs like a bulk inverter, filter, sensors for net meter, etc. But I argue that this is a one-time investment worth making. First, we have to start with small colonies in the metropolitans, then slowly diverge. Besides the reconstruction issues, I’ve seen numerous articles on how smart grids will be a security issue, how leaking a person’s peak-power-demand profile is a breach of privacy.
Well, I cannot but address it here. The power system has witnessed many ups and downs in its short life span. Ever since the birth of electricity back in the 1800s, it had been a matter of debate whether or not electricity is safe for the masses. There were even anti-electricity protests back then. 150 years have passed, but it’s crazy how the debate for electricity still persists. Maybe it is not as apparent, but it’s actually very similar. A person who owns a smartphone and uses Wi-Fi is far more exposed to security breaches than a smart grid can ever expose him. Smart grids come with numerous advantages over the existing power distribution system. Most importantly, at a point when the natural resources run out, we won't really have a choice but to opt for renewable energy sources. So why not start adapting to it now?
Smart grid allows us to gradually integrate renewable energy into the existing grid system. That’s why we have to educate the mass about the obvious benefits of the smart grid and renewable energy. The biggest enemy of innovation is assuming we are better off without it. We are, by no means, better off without a more efficient power system! So, we have to be open-minded about improving the existing power grid system by replacing it with a greener, smarter, and more efficient technology like Smart Grid.
References:
[1] “Booming Energy Sector Of Bangladesh: 90 Percent Have Access To The Electricity”. bdnewsnet.com. Dhaka, Bangladesh. Bangladesh News Network. 12 July 2018. Retrieved 17 July 2018. http://www.bpdb.gov.bd/bpdb/index.php?
[2] “Govt plans to sign energy pact with Bangladesh”. The Himalayan Times. 16 April 2018. Retrieved 9 May 2018.
[3] M. Hassan Shetol, M. Moklesur Rahman, RatneshwarSarder, M. Ismail Hossain, F. KabirRiday,Present status of Bangladesh gas fields and future development: A review,Journal of Natural Gas Geoscience,
[4]en.banglatribune.c om/business/news/89511/Gas-reserves-to-be-exhausted-in-11-years-Minister#:~:text=Bangladesh’s%20gas%20reserves%20will%20last,billion%20cft%20being%20extracted%20daily.
[5] Fang, Xi & Misra, Satyajayant & Xue, Guoliang & Yang, Dejun. (2012). Smart Grid — The New and Improved Power Grid: A Survey. Communications Surveys & Tutorials, IEEE. 14. 944–980. 10.1109/SURV.2011.101911.00087.
