<form action="" method="post" id="datiluce"  enctype="multipart/form-data">
Costo al kW/h : <input id="costo "name="costo" required="" type="number" />
Ore funzionam.: <input id="ore" name="ore" required="" type="number" />
gg funzionam.: <input id="giorni" name="giorni" required="" type="number" />
Potenza in KW : <input id="potenza" name="potenza" required="" type="number" />
Genere :<select id="luce" name="luce" required="">
<option selected="selected" value="Alogena">Alogena</option>
<option value="Fluorescenza">Fluorescenza</option>
<option value="Incandescenza">Incandescenza</option>
</select>
<button >Invia</button></form>
<div id="risultato"></div>