Sun fired pots with solar panels? Sort of…

While the cre­ation of pot­tery takes a good deal of ener­gy for min­ing, pro­cess­ing, mak­ing and fir­ing, ceram­ic ves­sels have the ben­e­fit of being long-last­ing and not harm­ful to the envi­ron­ment when dis­posed of. How­ev­er, any use of renew­able ener­gy in the process is good, so we decid­ed to invest in solar pan­els to con­tribute to our ener­gy use, par­tic­u­lar­ly in the the kiln firing.

We fire our pot­tery just once, by allow­ing the clay to dry out, apply­ing the glaze and then fir­ing it. The stan­dard way of fir­ing ceram­ics is to fire the items twice; first a bis­cuit fir­ing, then a glaze fir­ing. Raw glaz­ing does­n’t quite use half the ener­gy of the stan­dard fir­ing method, because the fir­ing is done over a longer peri­od of time, but it does use less energy.

Our elec­tric kiln has a slight­ly larg­er capac­i­ty of an old style gal­vanised dust bin. The fir­ing cycle uses 64kWh. Data from our solar pan­els for 3 years shows the aver­age dai­ly elec­tri­cal gen­er­a­tion is 6.25kWh. This means we can fire the kiln every 10 days with ener­gy derived from the sun.

Nat­u­ral­ly it isn’t that straight­for­ward. We can’t say we fire the kiln direct­ly from the sun, but if the Nation­al Grid is viewed as a bank, we can say we put ener­gy in the bank, save it up and with­draw it to use later.

Solar pan­els them­selves take ener­gy to create.

It is also use­ful to think what 64kWh of elec­tric­i­ty means. Accord­ing to Ofgem, the medi­um ‘Typ­i­cal Domes­tic Con­sump­tion’ of two pro­file class­es UK house­hold use around 8 kWh or 11 kWh of elec­tric­i­ty per day. This means we use between 6 and 8 days worth of elec­tric­i­ty used in a UK home for one fir­ing. (Accord­ing to Ofgem, UK house­holds also use around 33 kWh of gas per day).

The solar panels