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Groundbreaking Cement-Free Concrete a Game Changer in Construction
By
Tasos Kokkinidis
July 11, 2024
The cement-free concrete concrete is an environmentally friendly alternative to conventional cement. Credit: Dr. Vladimir Ronin, Creative Commons Attribution-Share Alike 3.0/Wikipedia
Cement-free concrete is a revolutionary material that aims to reduce the environmental impact of traditional concrete by eliminating cement from the mix. Cement production is a significant contributor to greenhouse gas emissions, so finding alternatives is crucial for sustainable construction.
Instead of cement, cement-free concrete uses other binding agents, often derived from industrial byproducts. Some common approaches include the Alkali-Activated Cementitious Materials (AACM) that activate pozzolanic substances like ground granulated blast-furnace slag (GGBS) and pulverized fly ash (PFA) to create a binding agent.
Other approaches include the steel slag using industrial waste and developing low-CO2 additives that can be mixed with excavation materials to create cement-free concrete.
Last year one of the first companies to use cement-free concrete, a first-of-its-kind innovation in the construction industry, was used in a commercial building project in Seattle.
More:
https://greekreporter.com/2024/07/11/groundbreaking-cement-free-concrete-debuts-in-seattle/
3 replies
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Last edited Sun Jul 21, 2024, 11:38 PM - Edit history (2)
from https://www.democraticunderground.com/10143004710#post7
Solar comes out very well on concrete, but terrible on steel, glass, and other.
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https://www.cnbc.com/2021/02/14/bill-gates-concepts-to-understand-the-climate-crisis.html?&doc=107178583
Land use efficiency, watts/square meter:
fossil fuel: 500 to 10,000,
nuclear: 500 to 1000,
solar: 5 to 20,
wind: 1 to 2 -- that's 1 to 2 MW per square kilometer
Amount of square kilometers needed to produce 1 GW (1,000 MW), calculated from above:
Fossil fuel: 0.1 to 2 square kilometers
Nuclear: 1 to 2 square kilometers
Solar: 50 to 200 square kilometers
Wind: 500 to 1,000 square kilometers
A square kilometer is 0.3861 square miles, A square mile is 2.590 square kilometers
As far as I know, the solar and wind figures above are for when they are the only use for the land they are on. In fairness, especially with wind, one can have wind turbines on actively-farmed farmland and grazing pastureland. There are also articles like on sheep grazing under solar panels, solar panels covering canals, and the like.
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While I'm at it, I'm reminded of this graphic (just so I have all this info that I know about in one place):
CO2 equivalent emissions of different power sources, grams/KWH (entire life cycle)
https://world-nuclear.org/information-library/energy-and-the-environment/carbon-dioxide-emissions-from-electricity
The site blocks one from seeing anything with an email solicitation but eventually that goes away, takes at least 30 seconds, grr
On a life-cycle basis, nuclear power emits just a few grams of CO2 equivalent per kWh of electricity produced. Whilst estimates vary, the United Nations (UN) Intergovernmental Panel on Climate Change (IPCC) has provided a median value among peer-reviewed studies of 12g CO2 equivalent/kWh for nuclear, similar to wind, and lower than all types of solar.2
Figure 1: Average life-cycle CO2 equivalent emissions (source: IPCC)