DIRECTION Site Valladolid

Country & City: 
  • Spain
  • Valladolid
Project: 
Contact Information: 
Sergio Sanz
Centro Tecnológico CARTIF
Spain

The Spanish demo site is located in the centre of Spain, under a Mediterranean Continental Climate. The building, known as CARTIF III, has 4,075 m² of floor space and will be used for CARTIF Technology Centre research activities, with both offices and test facilities.

The design and construction of the building follows the innovative approach of the DIRECTION project. Therefore, this demo site is a very low energy building that integrates different strategies and solutions for energy saving, therefore improving the overall energy efficiency.

Technological approach

  • Energy efficient buildings - new buildings:

The main façade is south oriented. Envelope minimizes thermal energy and light electrical demand through glass walls and louvers blinds, which improves solar gain and a blind with oriented louvers, fixed to optimize the daylight use and avoid glare;

High efficiency lighting;

Advanced building management system (BMS).

  • Photovoltaic:

45 kWp photovoltaic, which allows a contribution of 15 kWh/m²yr.

  • Heat pump:

Geothermal heat pump with seasonal performance for the office area, which allows to balance the energy absorbed from and dumped to the ground, so the annual thermal need to heat this area is null.

  • Biomass boiler:

A very high performance biomass boiler (> 90 %) provides all the necessary thermal energy for the industrial buildings and the Domestic Hot Water (DHW).

  • Mechanical ventilation and heat recovery:

Free-cooling system for the entire building that allows a considerable reduction in cooling requirements.

Key technical Performance Indicators - results

The Direction project main objective is to develop new buildings based on energy efficient concepts. Since there is no retrofitting of existing buildings and therefore, there is not existing data to compare the performance of the new systems, it is important to define a baseline based on the energy performance of reference buildings. This reference can be established either by state of the art or minimal requirements by law.

Therefore, the KPI for the new building are compared in the next sections with a baseline based on a reference building.

Energy Performance

As a result of the energy efficiency and RES interventions both thermal energy and electricity consumption are cut in half compared to the reference building as seen in Figure 1.

Figure 1: Final energy demand and consumption of reference, design and monitored building

Compared to the design data a reduction in final energy demand of 29 % can be achieved. In comparison with business-as-usual (reference building) the final energy savings amount to 53 % as seen in Figure 2.

Figure 2: Comparison final energy demand (reference and design) and final energy consumption (monitored)

Primary Energy and CO2-Emissions

For the assessment of primary energy requirements primary energy factors from the data collection sheets are available. For higher accuracy, the values used for the calculations on the project’s website are acquired in cooperation with the Cartif Energy Division. If not stated in neither data collection sheets nor project deliverables, desktop research is conducted and values from trustworthy sources used (see Figure 3).

Figure 3: Primary energy needed for reference, design and monitored building

As a result of interventions undertaken a total annual amount of 103.4 tonnes of CO2 (25.4 kgCO2/m²a) can be saved in comparison to the reference building. In relative numbers this is an emissions reduction of 70 %. The monitored CO2 emissions amount to 46 tonnes per year (11.26 kgCO2/m²a) (see Figure 4).

Figure 4: CO2 emissions of reference, design and monitored building

Key Financial Indicators

The investment costs and energy prices are extracted from the provided deliverables and analysed as to their validity. The electricity price for the year 2014 in Valladolid is 0.13 €/kWh for electricity (industry) and corresponds to values from Eurostat statistics. The energy price for wood chips with 30 % moisture is corrected from 0.21 (data collection sheet) to 0.021 €/kWh after intensive research. The energy price for grid-connected gas for 2014 is 0.037 €/kWh accord ding to Eurostat statistics. The payback period depends greatly on the energy prices used (household or industry). Considering the gas price alone, if the gas price for households is used, the payback period decreases by five years. With the provided information and calculated energy savings the payback period for design and monitoring data is calculated. For the payback period calculation of the demonstration site a discount rate of 3 % and an inflation rate for the energy carriers of 3 % is assumed.

Investments

The investment costs associated with energy efficiency and RES interventions amount to 544,660 € and are distributed across the interventions as stated in next table.

Table 1: Distribution of investment costs across interventions

Energy savings and energy cost savings

The total energy savings compared to the reference building are 177 MWh per year. The respective energy cost savings are 18,181 € per year with the reference building as the baseline. Compared to the design 3,378 € in energy costs are saved annually. The distribution of the energy and energy cost savings across energy usage is shown below.

Table 2: Energy and energy cost savings of monitored building compared to design and reference building

Payback period

Table 3: Payback period for designed and reference building as baseline

The total costs of the reference building are 3,463,301 € and those of the new building 4,113,378 €. With a cost difference of 650,077 € the payback period of the monitored building with the reference building as the baseline is 35.8 years  as shown in Table ‎3‑3. On the one hand, this value is higher than the average payback period of 30 years for eligible costs related to energy efficiency measures as stated in the European Commission decision from 2013. On the other hand, the longer payback period reflects the core energy efficiency measures with a longer life cycle (see IEA energy efficiency market report 2015) such as energy efficient insulation and other façade parts. The payback period of the monitored building with the designed building as the baseline is 46.6 years.

The same value for investment costs is used for the designed and monitored building. The calculation of the payback period ignores financial gains due to potential rental changes. That is why the potential for a lower payback period exists and would need a different analysis for a building in private hands. The payback period is a challenge and would need to be reduced if private replication is sought. What is unclear is the return to investment of the components, a factor that could be of importance.

Financial & Economic: 

The following barriers, key best practices, recommendations and solutions are at demo level and are collected within the DIRECTION Best Practices Book (http://bit.ly/1QW9AL4), some are general and not specific for this site.

  • Barriers: Fully centralised room control systems tend to generate a sense of frustration among the users.

Solutions: Involving tenants in the design process and giving them some flexibility in adjusting environmental parameters is therefore important. Motivating and empowering users to change their behaviour towards sustainability requires obtaining the right balance between centralized control and user freedom.

  • Barriers: Owners are reluctant to invest because it’s the tenants who pay the energy bills, whilst tenants don’t directly intervene in the building development phase as they don’t own the building.
    • Solutions: Showing energy efficiency benefits can trigger owner demand. Energy efficient solutions need to be demonstrated to building companies and owners so that they can understand the advantages brought about, and how investment costs can be offset by later earnings. The Nu-Office (Munich, Germany) implemented several energy saving measures that were able to predict energy consumption below the average office building consumption, thus offering tenants a “flat-rate charge” on consumption costs and generating a marketing advantage for the building.
  • Barriers: when dealing with public owners, the inclusion of public tenders is mandatory, which can make the process last even longer than expected.
    • Solutions: Public bodies should be aware of the specific risks when operating energy efficiency in buildings projects and impose flexible timetables while managing ambitious expectations.
    • Public bodies should be prepared to cooperate with research institutions in order to produce the detailed and specific documentation for tenders. Such collaboration should help public bodies define the technical aspects that will ensure project innovation.
  • Barriers: A new building’s potential in energy saving can only be fully exploited when everyday users get taught how to actively deal with these aspects and systems.
    • The opportunities for energy savings should be promoted as a personal green contribution and users should be encouraged through incentives and training to save energy.
  • Barriers: Changes of renewable energy production legislation. The feed-in-tariff scheme was amended. Prior to the legislation changes, RES producers were paid for producing electricity and feeding it to the grid. After the legislation changes, the amount of renewable energy produced in buildings and feeding the grid is restricted, any extra energy feeding the grid requires payment of a fee.

Lessons learnt:

  • Public bodies and developers should have the opportunity to be role-models and demonstrate that developing low-energy buildings is about environmental and economic opportunities pursued through a holistic planning process;
  • The Key Performance Indicators (KPIs) have to be carefully chosen and defined in order to help the project achieve its objectives. Defining the right KPIs and having a good monitoring plan will ensure that performance targets are met.

In Spain the change of the photovoltaic and auto-consumption legislation deeply affected the viability of the project. Controversial changes in the support schemes in Spain in 2010, 2013 and 2014, first abolished the feed in tariff and then introduced a fee to provide electricity to the grid. Over-production is no longer a revenue generating option, having been made economically non-viable.

As the buildings have no energy storage capacity, it was necessary to install regulators on the panels in order to limit electricity production, which means losing energy. An attempt has been made to divert some of the extra energy to other uses, such as making sure in advance that the building will not overheat during the summer. Nevertheless, the viability of the project has been damaged.