The use of methane as automotive fuel – a step to sustainable economy?

The introduction of CNG (Compressed Natural Gas) as automotive fuel began in Italy as early as in mid- 1930s, and ever since the Italian market has always been highly advanced in this regard. Many other countries followed, some of them quite recently, but nevertheless with impressive results. The appeal of this automotive fuel is based on the fact that compared to gasoline, diesel and LPG (Liquefied Petroleum Gas), CNG is cleaner and cheaper; even more so, this fuel is renewable – it can be produced locally from biogas. Despite its obvious benefits, CNG is barely present in Hungary. This article provides an insight into the topic, highlights obstacles to introduction and suggests appropriate governmental steps. The information is intended to support the activities and the decision-making process of governmental officials, municipalities, car-fleet managers, car dealers and their service departments.

Analyzing interrelated stochastic trend and seasonality on the example of energy trading data

The correct modelling of long- and short-term seasonality is a very interesting issue. The choice between the deterministic and stochastic modelling of trend and seasonality and their implications are as relevant as the case of deterministic and stochastic trends itself. The study considers the special case when the stochastic trend and seasonality do not evolve independently and the usual differencing filters do not apply. The results are applied to the day-ahead (spot) trading data of some main European energy exchanges (power and natural gas).

Analyzing interrelated stochastic trend and seasonality on the example of energy trading data

The correct modelling of long- and short-term seasonality is a very interesting issue. The choice between the deterministic and stochastic modelling of trend and seasonality and their implications are as relevant as the case of deterministic and stochastic trends itself. The study considers the special case when the stochastic trend and seasonality do not evolve independently and the usual differencing filters do not apply. The results are applied to the day-ahead (spot) trading data of some main European energy exchanges (power and natural gas).