Energy consumption of Aluminium Alloys

It is no secret that foundries are energy-intensive. The European industry is currently facing extreme challenges to compensate for increased energy prices.

Many parts now have razor-thin margins. Metal prices are usually adjusted to the market quarterly, so these costs can be charged to the customer. But energy costs have been stable for years and are normally not adjusted after the quotation years before the series starts. A doubling or even more in energy costs cannot be sustained on these margins. Everything else got more expensive with the inflation, too.

In foundries, aluminium ingots are melted together with internal scrap. It takes 657 kJ (=0,183 kWh) to heat a kilogram of aluminium to 750°C melting temperature, not including furnace inefficiencies or heat loss. It takes another 390 kJ (=0,108 kWh) to melt that kilogram of aluminium.

By casting, the liquid metal has to be held at a high temperature. Also, the tool is heated to reduce the temperature difference between the aluminium and steel surfaces. Then, the same energy as for the melting is required in the tool’s cooling capacity to solidify the casting quickly. It must cool even more than the solidification point to extract the part without deformation.

So, a lot of energy is needed to change the shape of the aluminium from an ingot to a part, and that energy has become way more expensive. In addition, sustainability requirements also emerge. The origin of the energy source also determines the carbon footprint of the production. Hydro and/or wind power have the lowest emissions.

Are you aware of your production’s energy consumption and carbon footprint? Schedule a free consultation to find ways to increase the recycled content and sustainability of your production.