1. Introduction
2. Daylight Saving Time (DST)
3. Domestic Lighting
4. Standards
5. FIDE Seal
6. Other Measures in Households
7. Capacity Building
8. Education
9. Distribution of Information
10. CONAE Internet Web-page
11. Other, Non-household Programmes

2. Daylight Saving Time (DST)

DST was adopted in 1996 and has been applied in all of Mexico from then on. Through DST, the time when lights are switched on is pushed one hour back. Thus, energy consumption is reduced by one hour of lighting per day, peak demand is moved and thereby reduced considerably. The diagram below illustrates this fact.

Figure 1: Impact of daylight saving time on peak demand

Energetic Impact

The Instituto de Investigaciones Eléctricas (IIE) each year evaluated the energetic impact of DST. Also, information of the Centro Nacional de Control de Energía (CENACE - National Energy Control Centre), was analysed from 1996 to 2001. The following results were obtained:

Table 1: Reduction of electric energy consumption by year. Source: FIDE

The other positive impact is that of a reduced peak load. Through the DST the required maximum capacity is reduced, so that without the system the current power plant capacity would not be sufficient to cover the peak load, and a large investment would be required to guaranty electricity supply during peak hours. Studies by FIDE and IIE reveal that through DST, the peak demand is reduced by 500 MW.

The reduction of maximum demand is reflected in the demand curves that Comisión Nacional de Electricidad (CFE - national utility) and Luz y Fuerza del Centro (LyFC - regional utility) generate each year. A comparison of the curves of 28 March (before DST) and 4 April (after start of DST) of the year 2000 in the central region of Mexico showed a reduction of 383 MW. (CONAE web-site)

Economic Impact

Through the DST scheme, each year substantial amounts of investments are saved, as shown in table 1 above.

Domestic tariffs in Mexico are subsidised with about 50 % of the average selling price. As the highest saving rates with DST are realised during peak hours (i.e., highest generation costs), it is estimated that approximately 2500 million Pesos of subsidies were saved from 1996 to 2000.

For industry, an important benefit resulting from this measure is the reduction of peak load tariff time for users with a demand of over 100 kW. Through the DST peak load time was reduced from three hours to only two hours in the evening, so that industries have to pay one hour of peak load tariffs less. 1 (CONAE web-site)

Environmental Impact

After six years of working with DST, more than 10 million tons of pollutants were avoided. The table below illustrates this fact.

Table 2: Reduction of pollutants through DST (CONAE web-site)