systems in mesoscopic physics, present our model and outline the strategy adopted to obtain the desired chain of quantum dots. Starting with  \[General properties\], we will work in the linear response regime and under the following main assumption: the scattering matrix $S$ associated to the system does not depend on the energy. As we shall see, this assumption, which is a good approximation in certain limiting cases, will lead to some interesting consequences.

More precisely, the main results of this paper are divided into three parts. In  \[General properties\], we present the general transport properties of the system, and discuss in particular the Onsager relations and the entropy production. In  \[The null currents condition\], we solve the self-consistency condition, we fix the boundary values $(T_\L,\mu_\L)$ and $(T_\R,\mu_\R)$, and adjust the parameters $(T_i,\mu_i)$, for $i = 1,\dots,N$, so that the net average electric and heat currents into all the intermediate reservoirs vanish. This condition leads to expressions for the temperature and chemical potential profiles along the system, which turn out to be independent of the nature of the particles, independent of the distribution describing the reservoirs. From these profiles, we work out the average electric and heat currents flowing through the 