This Brief Communication presents a series of model calculations for the electron pair donor densities required for <i>tresino</i> thermal energy generation in the Earth. The crucial density of electron donors is determined from the ratio of He<sup>3</sup> and He<sup>4</sup> after many years starting from initial densities of the donor pairs. In addition, a new proposal is introduced that connects Cooper pair formations to the deuteron <i>tresino</i> nuclear reaction chain (the chain that determines the He<sup>3</sup> / He<sup>4</sup> ratio). Furthermore, it is proposed that magnetotelluric (MT) observations may be connected to Cooper pair formation either with or without substantial heating.