A city of 100,000 people is not a big city, is actually quite a tiny one, so we don’t have to use a large amount of energy to power all the households, administrative buildings and companies headquartered there.
Usually, when we talk about powering a city of 100,000 residents, we talk about the number of households in the city that need to be powered.
How Many Megawatts To Power A City?
A city of 100,000 people contains about 50,000 households, and knowing that the average U.S. household consumes about 1,000 kWh (1 MWh) each month, and 12 MWh per year, we understand that to cover such a demand of energy we need to produce at least 600,000 MWh of clean and renewable energy each year.
To produce 600,000 MWh of energy per year using only renewable energy sources, we need to use a diversified source of renewable power.
Renewables Used To Cover the Power Demand of the City
Our portfolio would include green resources like hydropower, biomass, wind power and solar energy.
A power station that burns biomass to produce energy, usually consumes about 75 tons of biomass per hour to generate about 50 MW of energy.
During the year, the power station will burn about 400,000 tons of biomass (mainly wood chips) to produce about 265,000 MW of energy.
Burning wood chips require a large amount of wood every year, and we know that burning wood generates smoke, something similar to burning fossil fuels such as coal and oil.
So, why is biomass considered a renewable energy source? the answer is simple, trees regrow, the wood that is used to produce wood chips is harvested in a sustainable way.
Foresters will selectively harvest the trees to protect the birds living there and the habitats, and they usually take only the tops and the limbs of the trees to turn them into wood chips.
Replanting the trees is also done by the same foresters, and the forest also replants new trees by itself.
If the trees are selectively harvested and the forest is replanted, the wood resource will remain available for generations to come.
265,000 MW of clean power covers only about 44% of the energy demand in the city, and this means that we have to also use other sources of alternative energy to cover the power demand only using renewable energy sources.
The difference of 335,000 MW of clean energy per year required to cover city’s demand would be generated by hydropower, wind energy and solar power.
Today we see a major shift in the energy sector, because the old grid was not created to handle intermittent sources of power such as solar and wind.
The Grid Must Be Upgraded To Become A Smart Grid
The grid must be upgraded to allow users produce their own power and send the excess energy back to the grid, which means that we need a smart grid that for today’s advancements and for the future society.
The times when we used a giant power plant near or inside the city that burned fossil fuels to produce electricity for all the homes and businesses in the town will slowly be replaced with a system that will allow energy freedom for all the residents of the city.
The home of the future will create its own power by placing solar panels on the roof, a block of flats will become its own utility provider by installing on the top of the building solar PV systems and maybe small wind turbines to produce clean electricity for the entire building.
Such energy systems using the sunlight or the wind to produce clean power for free will become very popular among people and this will clean the atmosphere and the also the environment.
I like where you’re going with this, but your methods for determining the energy requirements for this fictional city are extremely flaw. Why have you only considered household energy usage? Is this a city with no commercial, institutional or industrial develop
Hi
is everyone here retarded? How is burning biomass good? What’s the difference between burning biomass , coal, oil, natural gas, etc??? by your logic they should all be considered renewables. Burning coal and wood is almost the same thing as they have the same carbon chains. The only difference is : coal has higher energy density than wood.
go back to school, start with first grade
I’d like to find out more about renewable energy.
I would be interested to find out more details because I want to use clean energy to power my factory.
I apologize; I was unable to post the full comment using your site’s system, nor able to post it in pieces. Here is a gist containing its text and sources:
gist.github.com/Fordi/6e1fbab65d2023ef63639c6e2532dfc8#file-response-to-how-to-power-a-city-md
(I assume that the primary reason for the high biomass deployment is simple: most renewables are intermittent, while biomass is not. The high deployment serves as “spinning reserve”, to deal with the continuously variable production of the other plants, and with continuously variable demand.)
The difference of 650,000 MWh of clean energy per year required to cover our city’s demand would be generated by hydropower, wind and solar. If we apportion equal money-per-erg to each type (without going into the total cost, for now), we can use the EIA’s LCoE[5] estimates³ to weight our deployment.
Since you didn’t include sources, and got your units all confused, I figured I’d try to rewrite some of this.
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We’ll use the United States as a model, as it will give us the “worst-case”. The US Population is about 323 million [1], and we consume about 3,900 TWh/year [2] across all sectors – so the per-capita demand for a US citizen and all the support she requires to live, is about 12 MWh/year. For our city of 100,000, therefore, we’ll need about 1.2 TWh/year of clean energy.
At a capacity factor of 50%¹, a power station that burns biomass to produce energy would consume about 500 tons of biomass per hour to generate about 50 MW of energy². During the year, the power station will burn about 3,000,000 tons of biomass (wood chips and pellets, agricultural waste, etc) to produce about 550,000 MWh of energy per year.
550,000 MWh of clean power represents only 46% of the energy demand of the city, so let’s see which are the other clean energy sources that we can use to cover the entire energy demand only from renewable energy sources.
Well, we are talking here about how much electricity does an American home use per year because we want to cover the demand of electricity using only clean energy produced by renewable energy sources.
Here is the source used to gather the info:
https://www.eia.gov/tools/faqs/faq.cfm?id=97&t=3
The numbers can be realistic for a town up to 100,000 residents, not more (like the entire U.S.)
If we are using the U.S. consumption per capita then yes, we need to cover a demand of 1.2 TWh/year.
You are wrong when you say that the biomass power station requires “…500 tons of biomass per hour to generate about 50 MW of energy.”
These figures are taken from an online source? how about a real biomass power station?
Have you heard about the Joseph C. McNeil Generating Station?
The McNeil biomass power station burns 76 tons of biomass per hour to generate 50 MW of energy.
https://www.burlingtonelectric.com/about-us/what-we-do/joseph-c-mcneil-generating-station
The choice is marginal, by these metrics – but there is the issue of that high biomass deployment. (see:newscientist.com/…/mg23130922-600-revealed…/). If going that direction, careful and mindful forestry is necessary over the long term. Similarly, careful and mindful operation is required of nuclear. A hybrid approach (what I normally prefer) would have most of the same advantages as either, but with greater robustness to changes in demand and environmental conditions.