Danish national plans for Nearly Zero Energy Buildings
E N E R G Y S E M I N A R I N E S P O O 5 N O V E M B E R 2 0 1 4
K I R S T E N E N G E L U N D T H O M S E N
D A N I S H B U I L D I N G R E S E A R C H I N S T I T U T E , S B i A A L B O R G U N I V E R S I T Y C O P E N H A G E N
• Political ambitions for new and existing buildings in Denmark
• Definition of and plans for Nearly Zero Energy Buildings (NZEB)
• Integration of renewable energy in NZEB
Agenda
Tu r n i n g t h e b a c k t o f o s s i l f u e l s :
2020 – 50% of electricity covered by wind energy 2030 – No more use of coal in power plants
2035 – All electricity and heating covered by renewable energy
2050 – All energy covered by renewable energy
(electricity, heating, transports, industry)
Political energy ambitions
• Broad coalition in the parliament agrees on a new energy agreement
• Set the directions until 2020
• Concrete initiatives on energy
infrastructure, taxation, conditions for energy intensive industries etc.
• AND it spells out the contents of a
strategy for energy renovations of the existing building stock
Energy Agreement – March 2012
62 actions in total
• More than 35% renewable energy in final energy consumption
• Approximately 50% of electricity
consumption to be supplied by wind power
• 7.6% reduction in gross energy consumption in relation to 2010
• 34% reduction in greenhouse gas emissions in relation to 1990
Energy Agreement – main goals in 2020
Strategy for energy retrofit of buildings - 2014
• Political ambitions support and strengthen the already developed measures in the field of
Renewable Energy Sources (RES) in buildings
• Voluntary classes included in the Building Code:
• Low energy class 2015
• NZEB 2020 class (also called Building class 2020)
• NZEB 2020 class regulates the building envelope, the total calculated energy consumption, indoor climate etc.
Some practical consequences
• I n t h e f i r s t v e r s i o n o f t h e D a n i s h B u i l d i n g R e g u l a t i o n s 2 0 1 0 o n l y p r o j e c ti o n s f o r 2 0 1 5 w e r e a v a i l a b l e
• A s a r e s u l t o f r e q u e s t s f r o m t h e b u i l d i n g i n d u s t r y a n d l o c a l b u i l d i n g s e r v i c e a u t h o r i ti e s , p r o j e c t i o n s f o r t h e 2 0 2 0 r e q u i r e m e n t s w e r e i n c l u d e d i n e a r l y 2 0 11
• T h e b u i l d i n g i n d u s t r y w a n t e d t o b e a b l e t o :
• practice to meet the requirements without risking t o l o o s e a b u i l d i n g p e r m i t i n c a s e t h e y d o n o t
c o m p l y w i t h f u t u r e r e q u i r e m e n ts
• start to develop components and materials that c o m p l y w i t h f u t u r e r e q u i r e m e n ts , t h u s d e c r e a s i n g t h e c o s t o f t h e s e i m p r o v e d p r o d u c t s w h e n t h e y b e c o m e m a n d a to r y
Tightenings of energy performance
requirements in Denmark
C a l c u l a te d p r i m a r y e n e r g y d e m a n d f o r h e a t i n g ,
v e n t i l a t i o n , d o m e s ti c h o t w a t e r, e l e c t r i c i ty f o r b u i l d i n g
o p e r a t i o n , e l e c t r i c i t y f o r l i g h t i n g ( n o n - re s i d e n t i a l ) , s y s t e m e ff i c i e n c y, i n t e r n a l e n e r g y t r a n s p o r t , a n d a p o t e n t i a l
o v e r h e a ti n g ( + 2 6 º C ) p e n a l t y m i n u s R E S c o n t r i b u ti o n .
• S t a n d a r d c o n d i t i o n s f o r b u i l d i n g u s e
• O n e c l i m a t e z o n e
• O n e n a t i o n a l t o o l f o r c a l c u l a ti n g e n e r g y p e r f o r m a n c e i n n e w a n d e x i s t i n g ( c e r ti f i c a ti o n ) b u i l d i n g s
• Tw o b u i l d i n g t y p e s , r e s i d e n ti a l a n d n o n - r e s i d e n t i a l
• P o s s i b l e t o o b t a i n a n e x t e n s i o n o f t h e e n e r g y f r a m e f o r s p e c i a l u s a g e o f n o n - r e s i d e n ti a l b u i l d i n g s
Energy frame
R e s i d e n t i a l
2 0 1 0
5 2 . 5 + 1 6 5 0 / A k W h / m ² y e a r
2 0 1 5
3 0 + 1 0 0 0 / A k W h / m ² y e a r
2 0 2 0
2 0 k W h / m ² y e a r
Energy frames 1
Non-residential
2010
71.3 + 1650/A kWh/m² year
2015
41 + 1000/A kWh/m² year
2020
25 kWh/m² year
1) Primary energy for: heating, ventilation, domestic hot water, electricity for building operation, electricity for lighting (non-residential), system efficiency, internal energy transport, potential overheating penalty - RES
Requirements for new buildings
2010 2015 2020
Q < = 5 W / m ² Q < = 4 W / m ² Q < = 3 . 7 W / m ²
Q < = 6 W / m ² Q < = 5 W / m ² Q < = 4 . 7 W / m ²
Q < = 7 W / m ² Q < = 6 W / m ² Q < = 5 . 7 W / m ²
Dimensioning
1heat loss through
opaque parts of the thermal envelope
1 storey
2 storeys
3+ storeys
2 0 1 0 2 0 1 5 2 0 2 0
F a c a d e w i n d o w s - 3 3 - 1 7 + 0
R o o f w i n d o w s - 1 0 + 0 + 1 0
E
ref= I · g
w– G · U
w= 196,4 · g
w– 90.36 · U
wE n e r g y g a i n f a c t o r i n k W h / ( m2y e a r )
Windows - and energy gain reference
I n b u i l d i n g s c o m p l y i n g wi t h L o w E n e r g y c l a s s 2 0 1 5 o r B u i l d i n g c l a s s 2 0 2 0 , t h e r m a l i n d o o r c l i m a t e m u s t b e d o c u m e n t e d v i a c a l c u l a t i o n s
I n d we l l i n g s , i n s t i t u t i o n s , o f f i c e s e t c . t h e t h e r m a l i n d o o r c l i m a t e m u s t n o t e x c e e d 2 6 ° C , e x c e p t d u r i n g a l i m i t e d n u m b e r o f h o u r s c o m p a r e d wi t h t h e r e f e r e n c e y e a r
F o r d we l l i n g s , a t e m p e r a t u r e o f 2 6 ° C m u s t n o t b e e x c e e d e d f o r m o r e t h a n 1 0 0 h o u r s p e r y e a r, a n d a t e m p e r a t u r e o f 2 7 ° C m u s t n o t b e e x c e e d e d f o r m o r e t h a n 2 5 h o u r s p e r y e a r
D o c u m e n t a t i o n f o r t h e t h e r m a l i n d o o r c l i m a t e c a n b e d o n e ac c or ding t o “ DS 474 - Nor m f or s pec if ic at ion of t he t her mal indoor c limat e” us ing dy namic s imulat ion t ools
F o r d w e l l i n g s p r o o f c a n b e p r o v i d e d v i a a s i m p l i f i e d c a l c u l a t i o n i m p l e m e n t e d i n t h e c o m p l i a n c e c h e c k i n g t o o l B e 1 0 – B uildings e n e r g y d e m a n d 2 0 1 0
Thermal indoor climate
Air-change must not exceed X.X l/s per m²
(heated floor area) demonstrated at a pressure difference of 50 Pascal
2010 2015 2020 Tested air -change: 1.5 1.0 0.5
The municipality must require a pressure test in more than 5% of all new buildings
Fulfilment of 2015 or 2020 regulations always require a pressure test
Airtightness
Denmark operates with an energy frame, setting a limit for the allowed primary energy demand per m²
• Renewable energy (deducted from the primary energy demand) is locally produced heat (solar thermal) and electricity (PV and wind)
• Bio-fuels are treated in the energy frame as fossil fuels
• Heat pumps are electric heating systems with high efficiency
Renewable energy
L o c a l l y p r o d u c e d e l e c t r i c i t y c a n o n l y b e d e d u c te d i n t h e e n e r g y f r a m e u p t o t h e a m o u n t o f e l e c t r i c i ty u s e d f o r
o p e r a t i n g t h e b u i l d i n g , i . e . e l e c t r i c i t y f o r p u m p s , f a n s , h e a t p u m p s , a n d l i g h t i n g ( n o n - r e s i d e n ti a l b u i l d i n g s o n l y ) T h e b a l a n c i n g p e r i o d f o r l o c a l l y p r o d u c e d e l e c t r i c i t y i s m o n t h l y, t h o u g h u p t o t h e t o t a l m o n t h l y c o n s u m p ti o n o f e l e c t r i c i t y i n t h e b u i l d i n g
• T h e e c o n o m i c b a l a n c i n g p e r i o d f o r l o c a l l y p r o d u c e d e l e c t r i c i t y i s h o u r l y
• T h e c u r r e n t f e e d - i n t a r i ff f o r p r i v a t e h o u s e h o l d s i s 0 . 0 8 €/kWh while the price for buying electricity from t h e g r i d i s a p p r o x . 0 . 3 0 €/kWh
Local electricity production
In this context ”nearby” means within the same m u n i c i p a l i t y a s w h e r e t h e b u i l d i n g i s l o c a t e d
For buildings close to a municipality border “nearby” can a l s o b e i n t h e n e i g h b o u r m u n i c i p a l i t y, a s l o n g a s t h e R E S i n s t a l l a t i o n i s l o c a t e d i n t h e i m m e d i a t e v i c i n i t y o f t h e
b u i l d i n g
RES must be produced ”nearby”
F o r g ro u p s o f b u i l d i n g s t h a t c o mp l y wi t h Bu i l d i ng c l a s s 2 0 2 0 , i t i s a l l o we d t o e s t a b l i sh a j o i n t RES
i n s t a l la t io n a t t h e t i me o f c o n s t ru c t io n a n d i n c l u d e i t i n t h e e n e rg y f ra me
I t i s a p re re q u i s i t e t h a t t h e b u i l d i ng o wn e r c o n t ri b u t e s e c o n o mi c a l ly t o t h e i n s t a l l at io n a n d t h a t i t i s
established “nearby” the group of buildings
J o i n t s o l a r t h e rma l s ys t e ms c a n t h o u g h o n l y b e d e d u c t e d i n t h e e n e rg y fra me o u ts i d e d i s t ri c t h e a t i n g a re a s
Joint RES installations
T h e re a re n o s p e c i f ic t a rg e t f o r t h e s h a re o f l o c a l ly p ro d u c e d RES i n Da n i s h NZ EB
I n b u i l d i n g s wi th a l a rg e c o n s u mp ti o n o f DHW, i .e . + 2 0 0 0 l i t e rs / d ay, a s o l a r h e a t i n g s ys t e m i s re q u i re d (va l i d f o r b o t h c u rre n t a n d NZ EB re q u i re me n t s )
I n 2 0 2 0 , i t i s e xp e c t e d t h a t t h e Da n i s h e n e rg y mi x wi l l c o n t a i n a mi n i mu m o f 5 1 % RES – and all buildings
wi l l t h u s b y d e f a u l t (o n a ve ra g e ) h a ve a + 5 0 % RES s h a re
• Primary energy factors (PEF) will change a c c o rd i n g ly
L o c a l RES p ro d u c t i o n wi l l a d d t o t h e t o t a l RES s h a re i n t h e b u i l d i n g
RES in NZEBs Energy Performance
• Primary energy factors will be lowered over
time as RES will make up a larger proportion of the energy mix
• Electricity: 2.5 → 1.8
• District heating: 1.0 → 0.6
• Gas, oil, biomass: remains 1.0
• Renewable energy: remains 0.0
• Energy from RES installations can be
subtracted when calculating the overall energy consumption, but only limited – e.g. only
electricity for building operation in dwellings
Integration of renewable energy in
NZEB 2020 class
Primary energy factors in Denmark
0,0 0,5 1,0 1,5 2,0 2,5 3,0
2010 2015 2020
Development in Danish primary energy factors
Other District heating Electricity
